A method and system for batching commands and status information between a host computer and an adapter installed on the host computer. The method for command batching includes the host storing command pointers, each command pointer pointing to a command in an array, and providing an array pointer to the array. When a predetermined threshold of stored commands has been reached, the host can deliver a multitude of commands via the array pointer with a single bus access. A method for status batching includes transferring command statuses from the adapter to the host computer and providing a pointer to the transferred statuses. When a predetermined threshold of statuses has been reached, the adapter interrupts the host computer once to fetch the pointer and the host can then read the statuses without requiring any more bus interrupts.

Computing systems generally include a system bus for inserting input/output (I/O) interface circuits to connect the computing system to peripheral I/O devices. Such circuits are often known as host adapters, I/O interfaces, or I/O processors (IOP). The current trend for high-end networking and storage technology is pushing more functionality down to a low level driver, while at the same time demanding higher performance. To meet these demands, hardware vendors have developed intelligent host adapters that contain their own I/O controller circuits and associated processing capability for processing I/O transactions such as for RAID controllers. Intelligent host adapters may include significant local processing power and local memory use for processing host computer I/O requests and for controlling the attached I/O devices. New I/O architectures have been developed incorporating intelligent host adapters to relieve the host of interrupt intensive I/O tasks greatly improving I/O performance and high bandwidth applications, such as client server processing.
One such I/O architecture is known as intelligent I/O (I2O). The I2O standards are published and maintained by an industry group known as the I2O Special Interest Group. The I2O Standard, Version 2, can be found at "www.intelligent-IO.com." The I2O interface standard defines layers of an interface structure between, for example, the host computer system and an intelligent host adapter. The standard simplifies the device driver modules for I/O interface devices by isolating device dependencies in the modules. Driver modules written in conformance with the standard are also more portable among a variety of system architectures and operating systems. The I20 specification partitions the device driver into a first portion that contains all the Operating System (OS) specific code and a second portion containing all the hardware specific code unique to a particular class of I/O device. Accordingly, OS vendors need only produce one OS specific module for each class of an I/O device. Similarly, hardware vendors only need to produce a single version of the hardware device modules for a specific I/O adapter. In this manner, the I2O standard provides an I/O device driver architecture that is independent of both the I/O device and the host operating system.
A typical I2O driver consists of an operating system specific module (OSM) and a hardware device module (HDM). The OSM and the HDM are autonomous and can perform independent tasks without sending data over a system I/O bus in the host computer. An HDM and OSM interface with each other through a communication system comprised of a message layer and a transport layer. This communication system is similar to a connection oriented networking protocol. For example, in a connection oriented network protocol, two parties interested in exchanging information utilize a message layer to set up a connection and to exchange control information and data. In the I2O model, the message layer sets up a communication session between the HDM and the OSM and the corresponding transport layer defines how the HDM and the OSM share information.
In a typical application, when the OSM is presented with a request from the host operating system, it translates the request into an I2O message and dispatches it to the appropriate HDM for processing. When the HDM has completed the request, it dispatches the results back to the OSM by sending a message to the I2O message layer. The host layers in an I2O host system and an I2O intelligent adapter communicate with one another via shared memory data structures. Shared memory is accessible via the common system bus interconnecting the communicating nodes, for example, the host system and the intelligent adapter. Specifically, the I2O interface defines a number of standard queues and other data structures commonly accessible in memories shared between the respective processors and the host system and the intelligent adapters.
The peripheral component interconnect (PCI) bus has become a popular system bus for direct connection of host adapters to the host system. In such a system, the host system may directly access the local memory of the host adapter. Similarly, the host adapter may directly access the memory of the host system. Using such direct access to one another's memory, it is common to use direct memory access (DMA) in host adapters to perform the transfers of data with minimal overhead imposed on the general purpose processing power both the host system and the host adapter.
The I2O standard includes four circular queues for messaging: 1) an inbound free queue, 2) an inbound post queue, 3) an outbound free queue and (4) an outbound post queue. The inbound queues allow the host to obtain a pointer to a buffer by reading the inbound free queue and writing the message to this buffer. Once the message is written, the pointer to the buffer is written to the inbound post queue. Conversely, the outbound queues are used for the adapter's firmware to deliver returned message status to the host in a similar fashion as the inbound queues. For example, when the host needs to deliver a command to the adapter, the host sets up the command in the host's memory and then writes the command's address to the inbound post queue. In this technique, the adapter device driver immediately writes the pointer of this command to the inbound post queue requiring the device driver to access the PCI bus for each individual command delivery. In a system where multiple adapters are installed, the time the device driver spends in kernel privileged time may be extended due to other bus masters contending for access to the PCI bus.
Upon detecting a write to the inbound post queue, the adapter interrupts the adapter firmware. The firmware in turn pops the command address from the inbound post queue, sets up a DMA channel to fetch the command and processes the command. When the command is processed, the commands two status bytes and the command's ID are pushed onto the outbound post queue. When the adapter detects the availability of valid entries in the outbound post queue, the adapter sets a status bit in the outbound interrupt status register and sends an interrupt to the host. The host interrupt service routine (ISR) reads the status from the outbound message queue to process the status and thereby completes the cycle of command and status returned. The ISR can keep reading the outbound post queue until it receives a value of 0xffffffff that indicates the depletion of the outbound post queue's valid entries. Although multiple statuses are in the outbound post queue, the device driver's ISR must access the PCI bus and read the status from the outbound queue once per each status. With multiple adapters on a system, the device driver is contending with all other adapters for PCI bus resources. While the ISR is waiting for bus access, the ISR is tying up host CPU resources for servicing the ISR. In addition, due to speed mismatches between the host and the adapter, the ISR may read the first status and process the status before the adapter can replenish its staging status register from the status queue in local memory. During replenishment of the status register, the ISR is informed with an empty status (0xffffffff) and exits the routine. Once the status register is replenished after the ISR has exited, the bus needs to be interrupted again, requiring another ISR which may result in interrupt thrashing until the status queue is cleared.


The present invention relates to elastic articles comprising a crosslinked or crosslinkable ethylene polymer and a method for making the same. In particular, the invention relates to a shaped article (e.g. film or fiber) characterized by improved elasticity at elevated temperatures and comprising a substantially cured, irradiated, or crosslinked (or curable, irradiated or crosslinkable) homogeneously branched ethylene polymer. The improved elastic article of the present invention is particularly suitable for use in applications where good elasticity must be maintained at elevated temperatures such as, for example, personal hygiene items and disposable infection-control garments at body temperatures of about 100xc2x0 F. (38xc2x0 C.).

The present invention relates to a crosslinked, heat resistant elastic article having elevated temperature elasticity comprising a cured, irradiated or crosslinked ethylene polymer and a method for making a crosslinked, heat resistant elastic article. In particular, the invention relates to a shaped article (e.g. film or fiber) characterized by heat resistance and improved elasticity at elevated temperatures and comprising a substantially cured, irradiated, or crosslinked homogeneously branched ethylene polymer. The improved elastic article of the present invention is particularly suitable for use in applications where good elasticity must be maintained at elevated temperatures such as, for example, personal hygiene items and disposable infection-control garments at body temperatures of about 100xc2x0 F. (38xc2x0 C.).
Materials with excellent stretchability and elasticity are needed to manufacture a variety of disposal and durable articles such as, for example, incontinence pads, disposable diapers, training pants, sport apparel and furniture upholstery. Stretchability and elasticity are performance attributes which function to effectuate a closely conforming fit to the body of the wearer or to the frame of the item. It is desirable to maintain the conforming fit during repeated use, extensions and retractions at body temperatures. Further, for incontinence articles, stretchability and elasticity are particularly desirable to ensure comfort and provide security against unwanted leaks.
Disposable articles are typically elastic composite materials prepared from a combination of polymer film, fibers, sheets and absorbent materials as well as a combination of fabrication technologies. Whereas the fibers are prepared by well known processes such as spun bonding, melt blowing, melt spinning and continuous filament wounding techniques, the film and sheet forming processes typically involve known extrusion and coextrusion techniques, e.g., blown film, cast film, profile extrusion, injection molding, extrusion coating, and extrusion sheeting.
A material is typically characterized as elastic where it has a high percent elastic recovery (i.e., a low percent permanent set) after application of a biasing force. Ideally, elastic materials are characterized by a combination of three important properties, i.e., a low percent permanent set, a low stress or load at strain, and a low percent stress or load relaxation. That is, there should be (1) a low stress or load requirement to stretch the material, (2) no or low relaxing of the stress or unloading once the material is stretched, and (3) complete or high recovery to original dimensions after the stretching, biasing or straining is discontinued.
Lycra (spandex) is a segmented polyurethane elastic material which is known to exhibit goodelastic properties. But Lycra tends to be extremely cost prohibitive for a many of applications. Also, Lycra like natural rubbers tend to exhibit poor environmental resistance to ozone, chlorine and high temperature, especially in the presence of moisture.
Natural rubbers, as discussed by Ferdinand Rodriguez in Principles of Polymer Systems, pp. 242-43, McGraw-Hill (1982), the disclosure of which is incorporated herein by reference, generally show decreases in elongation to break with increase in degree of crosslinking. Furthermore, at high degrees of crosslinking, even tenacity at break may decrease for natural rubbers.
Elastic materials such as films, strips, coating, ribbons and sheet comprising at least one substantially linear ethylene polymer are disclosed in U.S. Pat. No. 5,472,775 to Obijeski et al., the disclosure of which is incorporated herein by reference. But U.S. Pat. No. 5,472,775 does not disclose the performance of these materials at elevated temperatures (i.e., at temperatures above room temperature).
WO 94/25647 (Knight et al.), the disclosure of which is incorporated herein by reference, discloses elastic fibers and fabrics made from homogeneously branched substantially linear ethylene polymers. The fibers are said to posses at least 50 percent recovery (i.e., less than or equal 50% permanent set) at 100 percent strain. But there is no disclosure in WO 94/25647 regarding the elasticity of these fibers at elevated temperatures, nor is there any disclosure regarding resistance to high temperatures.
U.S. Pat. No. 5,322,728 to Davey et al., the disclosure of which is incorporated herein by reference, discloses elastic fibers comprised of single site catalyzed ethylene polymers. But polymers are not cured, irradiated or crosslinked and therefore are believed to exhibit poor elevated temperature elasticity.
WO 95/29197 (Penfold et al.), the disclosure of which is incorporated herein by reference, discloses curable, silane-grafted substantially ethylene polymers which are useful for use in wire and cable coatings, weather-stripping and fibers. WO 95/29197 reports examples which include fibers comprising silane-grafted substantially ethylene polymers having densities of 0.868 g/cm3 and 0.870 g/cm3. While example fibers are shown to exhibit improved elastic recovery at elevated temperatures, there is no disclosure regarding percent stress or load relaxation performance at elevated temperatures.
U.S. Pat. No. 5,324,576 to Reed et al., the disclosure of which is incorporated herein by reference, discloses an elastic nonwoven web of microfibers of radiation crosslinked ethylene/alpha olefin copolymers, preferably having a density less than 0.9 g/cm3. The examples reported in U.S. Pat. No. 5,324,576 comprise ethylene polymers having polymer densities greater than or equal to 0.871 g/cm3 which subjected to electron beam radiation. But Reed et al. provide no disclosure regarding the elastic performance of these radiated polymers at elevated temperatures.
U.S. Pat. No. 5,525,257 to Kurtz et al., the disclosure of which is incorporated herein by reference, discloses that low levels of irradiation of less than 2 megarads of Ziegler catalyzed linear low density ethylene polymer results in improved stretchability and bubble stability without measurable gelation.
U.S. Pat. No. 4,425,393 to Benedyk et al., the disclosure of which is incorporated herein by reference, discloses low modulus fibers having diameters in the range of 0.5 to 3 mils (about 1 to about 37 denier).
Canadian Patent No. 935,598 to Hardy et al., the disclosure of which is incorporated herein by reference, discloses elastic fibers comprised of various ethylene polymers wherein the fibers are post-drawn (stretched) and crosslinked while under tension.
U.S. Pat. No. 4,957,790 to Warren, the disclosure of which is incorporated herein by reference, discloses the use of pro-rad compounds and irradiation to prepare heat-shrinkable linear low density polyethylene films having an increased orientation rate during fabrication. In the examples provided therein, Warren employs Ziegler catalyzed ethylene polymers having densities greater than or equal to 0.905 g/cm3.
In spite of various disclosures relating to elastic ethylene polymer articles, including articles comprising curable, radiated and/or crosslinked ethylene polymers, there is a present need for cost-effective elastic articles having good heat resistance and elasticity at elevated temperatures, especially at human body temperatures of about 100xc2x0 F. There is also a need for a method of making elastic articles having good elasticity at elevated temperatures. We have discovered that these and other objects can be completely met by the invention herein described.
We have discovered that elastic articles comprising a substantially cured, radiated or crosslinked ethylene polymer wherein the polymer is characterized as having a polymer density of less than 0.89 g/cm3, especially less than 0.87 g/cm3 and most especially less than or equal to 0.865 g/cm3 (or a differential scanning calorimetry (DSC) crystallinity at 23xc2x0 C. of less than 26weight percent, especially 12 weight percent, and most especially less than or equal to 8.5 weight percent). These novel articles exhibit excellent elasticity at room temperature and at elevated temperatures.
The broad aspect of the invention provides a heat resistant, shaped cured, irradiated or crosslinked article comprising an ethylene interpolymer of ethylene interpolymerized with at least one other monomer and characterized as having:
a) a polymer density of less than 0.89 g/cm3 or a DSC crystallinity at 23xc2x0 C., as determined using differential scanning calorimetry, of less than 26 weight percent before being shaped, cured, irradiated or crosslinked and
b) in meltspun fiber form, a value less than 0.75 for the expression
Abs[xcex94E/E0]+Abs[xcex94T/T0]
where xcex94E and xcex94T are taken from a stress-strain plot, as determined using an Instron tensiometer at 500 mm/minute crosshead speed and 10.2 cm gage length and from the average of four replications of five fiber samples; xcex94E is taken as the difference in percent elongation between the cured, irradiated or crosslinked polymer and the uncured, irradiated or uncrosslinked interpolymer at a tenacity of 0.4 grams/denier; E0 is taken as the percent elongation of the uncured, irradiated or uncrosslinked interpolymer at a tenacity of 0.4 grams/denier; xcex94T is taken as the difference in tenacity (in grams/denier) between the cured, irradiated or crosslinked polymer and the uncured, irradiated or uncrosslinked polymer at a percent elongation of 300 percent; T0 is taken as the tenacity (in grams/denier) of the uncured, irradiated or uncrosslinked interpolymer at a percent elongation of 300 percent; and Abs denotes absolute value.
Another aspect of the invention is a heat resistant cured, irradiated or crosslinked elastic fiber comprising ethylene interpolymerized with at least one other monomer wherein the interpolymer is characterized as having:
a) polymer density of less than 0.89 g/cm3 or a crystallinity at 23xc2x0 C., as determined using differential scanning calorimetry, of less than 26 weight percent before being shaped, cured, irradiated or crosslinked and
b) in meltspun fiber form, a value less than 0.75 for the expression
Abs[xcex94E/E0]+Abs[xcex94T/T0]
where xcex94E and xcex94T are taken from a stress-strain plot, as determined using an Instron tensiometer at 500 mm/minute crosshead speed and 10.2 cm gage length and from the average of four replications of five fiber samples; xcex94E is taken as the difference in percent elongation between the cured, irradiated or crosslinked polymer and the uncured, irradiated or uncrosslinked interpolymer at a tenacity of 0.4 grams/denier; E0 is taken as the percent elongation of the uncured, irradiated or uncrosslinked interpolymer at a tenacity of 0.4 grams/denier; xcex94T is taken as the difference in tenacity (in grams/denier) between the cured, irradiated or crosslinked polymer and the uncured, irradiated or uncrosslinked polymer at a percent elongation of 300 percent; T0 is taken as the tenacity (in grams/denier) of the uncured, irradiated or uncrosslinked interpolymer at a percent elongation of 300 percent; and Abs denotes absolute value.
A third aspect of the invention is a heat resistant shaped elastic article which comprises at least one ethylene interpolymer which has been cured, irradiated or crosslinked wherein the interpolymer comprises ethylene interpolymerized with at least one other monomer and is characterized as having:
(a) a polymer density of less than 0.87 g/cm3 before being shaped, cured, irradiated or crosslinked,
(b) a percent permanent set of less than or equal 25 at 23xc2x0 C. and 200 percent strain when measured at a 2 mil thickness using an Instron tensiometer after being shaped, cured, irradiated or crosslinked,
(c) a percent stress relaxation of less than or equal 25 at 23xc2x0 C. and 200 percent strain when measured at a 2 mil thickness using a Instron tensiometer after being shaped, cured, irradiated or crosslinked, and
(d) a percent stress relaxation of less than or equal 55 at 38xc2x0 C. and 200 percent strain when measured at a 2 mil thickness using an Instron tensiometer after.
A fourth aspect of the invention is a method of making an elastic article comprising the steps of
(a) providing an ethylene interpolymer having a density of less than 0.87 g/cm3,
(b) fabricating the article from the interpolymer, and
(c) after the fabrication, subjecting the article to heat or ionizing radiation or both.
A fifth aspect of the invention is a method of making an elastic article comprising the steps of
(a) providing an ethylene interpolymer having a density of less than 0.87 g/cm3,
(b) incorporating a pro-rad crosslink additive into the interpolymer,
(c) fabricating the article from the interpolymer, and
(d) after fabrication, subjecting the article to heat or ionizing radiation or both.
Preferably, the article is fabricated using an extrusion technique (i.e., the method consists of melting the interpolymer). Suitable extrusion techniques include, but are not limited to, fiber melt spinning, fiber melt blowing, film blowing, cast film, injection molding, or rotomolding technique. Preferably, the extrudate, filament, web or part is permitted to cool or is quenched to ambient temperature (i.e., permitted to substantially solidify) before the application of additional heating or ionizing radiation.
In a preferred embodiment of the invention, the ethylene polymer is a homogeneously branched ethylene polymer, especially a substantially linear ethylene polymer. In another preferred embodiment, the ionizing radiation is provided by electron beam irradiation.
We discovered that (unlike natural rubbers) curing, irradiation or crosslinking (increased crosslink densities) do not decrease the elongation at break or tenacity at break for homogeneously branched ethylene polymers having a polymer density of less than 0.89 g/cm3 and that articles (especially fibers) of cured, irradiated or crosslinked-homogeneously branched ethylene polymers exhibit substantially improve heat resistance.
We also discovered that there is a subset of ethylene polymers which provide completely unexpected elastic performance results when cured, radiated or crosslinked. In particular, we found for the broad range of polymer densities above and below 0 0.87 g/cm3, curing, radiation or crosslinking dramatically decrease percent permanent set performance (i.e., improve elasticity or elastic recovery) and have no substantial effect on ambient percent stress or load relaxation performance. But while tending to adversely affect (i.e., increase) or have no effect on percent stress or load relaxation at elevated temperatures for polymer having densities equal to or greater than 0.865 g/cm3, surprisingly curing, radiation and crosslinking decreases (i.e., improves) the elevated temperature percent stress or load relaxation performance of ethylene interpolymer having a polymer density less than 0.87 g/cm3 or a DSC crystallinity at 23xc2x0 C. less than 12 weight percent. That is, curing, radiating or crosslinking is an effective means for providing elastic materials and articles characterized as having excellent elevated temperature stress relaxation characteristics.
Not only is the dramatically different response to irradiation or crosslinking surprisingly in itself, these results are surprising for other reasons as well. For example, these results are surprising and unexpected because at a density of 0.87 g/cm3, ethylene polymers are already substantially amorphous. That is, a cross-over or transition in elastic performance attributable to curing, radiation or crosslinking would ordinarily be expected to relate to the amorphosity of the polymer; but according to hexane extraction data at 50xc2x0 C., determined according to the Food and Drug Administration (FDA) test method set forth under 21 37 C.F.R. xc2xa7xc2xa7177.1520 (d)(3)(ii), ethylene polymers are substantially amorphous at a density of 0.89 g/cm3 and below. Given such small differences in amorphosity or crystallinity, dramatic elasticity differences in response to irradiation or crosslinking simply would not ordinarily be expected.
Accordingly, the shaped elastic articles of present invention exhibit a unique combination of properties such as tenacity at break, elongation, elastic recovery, chlorine and aromatic/polar solvent resistance, moisture resistance, heat aging and excellent high temperature mechanical performance compared to traditional elastic materials, for example, natural rubber and spandex.

Articles having elevated temperature elasticity made from irradiated and crosslinked ethylene polymers and method for making the same


An apparatus for receiving a data stream consisting of a simultaneous plurality of time domain spread spectrum messages in the same frequency channel, wherein each message is independent and spread spectrally with a unique code. The data stream contains a subset of all known codes in use. The apparatus finds a specific code and a constant phase shift between the incoming code and a reference code by serially moving the data stream through a shift register, subjecting all the shift register outputs to a single expected reference code and accumulating the result for each output. The code and phase shift is indicated by the largest magnitude of the accumulation, above a set threshold, corresponding to the shift register output for the correct phase shift between the incoming code and the reference. Upon completion of an integration cycle the time shift delay increases by the length of the shift register. The process continues for all the possible relative time shifts and for all the reference codes.

This invention relates to spread spectrum communication of a plurality of messages recieved simultaneously, from different sources and particularly where the communications employ one of several pseudo random codes at baseband or on a carrier frequency and where the data communicated can be recovered only by the identification of the particular code and its time of arrival.


A television recorder defines a recessed memory storage device bay and a rack mounted in the memory storage device bay. The recorder includes a carrier for removeably locking a hard disk drive into the rack. The television recorder connects with a television and television broadcast source for simultaneously recording television programming and replaying recorded programming. The carrier engages the rack to removeably insert the hard disk drive into the television recorder.

ReplayTV, Inc. and TiVo, Inc. have developed television recorders incorporating media switches. In time, it is expected that these recorders will replace traditional VCR technology. Instead of recording a television input stream directly to a magnetic tape, these television recorders record and convert the television input streams, manipulate the input stream into digital data, convert the digital data stream into a television output stream, and selectively play back the output stream to a television. A hard disk drive is used to record both the input stream and to play back the output stream.
Many advantages that are realized through the use of hard drive media in combination with a television recorder having a media switch. ReplayTV, Inc. outlines some of the advantages on their web site www.replaytv.com:
Watch your favorite TV programming—on your schedule. ReplayTV will forever change the way you watch television. It sets you free from those TV schedules that are never where you left them. It pauses live TV. It records without videotape. It lets you skip over the boring parts. It searches and records shows with the touch of a button. It gives you control over live television. With ReplayTV, you can digitally record up to 30 hours of the shows you want to see and then watch them whenever you want. What doesn't ReplayTV give you? A monthly bill.
Pause Live TV (and perform other cool tricks). Watching your favorite tennis stars in a doubles match? Pause live programming to answer the phone or grab a snack—then resume watching without missing a single forehand crush or masterful lob. Bored with a rain delay? Skip ahead to get to the action. Want a closer look at a crucial line call? Use multispeed forward and reverse to get there, then catch every detail in Slo-Mo and frame advance. (And feel free to disagree with the referee!)
Go wherever you want at warp speed. Want to skip a scene that's too long or just plain boring? Use QuickSkip™ to jump forward to the good stuff. Plus you can digitally fast forward and rewind at 2 to 20 times normal speed. Now that's power. Are you starting to feel omnipotent yet? Read on.
Not sure what you're in the mood for? No problem. ReplayZones let you browse through more than 100 show categories—it's the easiest way to find the best of any television genre. Whether it's Sitcoms, Cartoons, Four Star Movies or Biographies, ReplayTV puts them all at your fingertips.
Know what you want? Find it fast. If you can spell "ER," ReplayTV can find it-instantly. With the Find Shows feature, you type in a show title or for that matter any keyword and, POW! up comes a list of every single show that matches your search. Find Shows even gives you a description of each show it's found so you can decide which ones to record. Tap the Record button and ReplayTV will do the rest.
The first day you own ReplayTV is the last day you watch boring television. Check out the on-screen Channel Guide, a complete listing of everything that's on for the coming week. When you find a show you like, simply press the Record button—it's that easy. Press it twice and ReplayTV will record that show every time it's on.
Live Instant Replay, Slow Motion, and Frame-by-Frame Advance. Okay, so the good guys somehow escaped the jaws of death—but it all happened so quickly, you missed a part. Tap the Instant Replay button and watch the last crucial 7 seconds again. And again. And again. Still puzzled about our heroes' escape? Dissect the scene using the digital Slow Motion or Frame-by-Frame Advance. So that's how they saved the world and fell in love!
Say "so long" to the VCR Programming Blues. Recording with ReplayTV is easy—no, really. Highlight a show, press the red record button once, and the show is recorded once. Press twice, and your show is automatically recorded every week. This means you'll never miss your favorite show again! Not only that ReplayTV digitally records up to 30 hours of programming.

This patent is subject to a terminal disclaimer.

Television recorder having a removable hard disk drive


A new Osteospermum plant named ‘Osectradepu’ particularly distinguished by its trailing, very vigorous growth habit, its deep purple colored flowers, facing upwards and its strong heat tolerance.

The present invention relates to a new and distinct cultivar of Osteospermum plant, botanically known as Osteospermum ecklonis. The new Osteospermum is propagated by cuttings resulting from an open pollination of a proprietary Osteospermum ecklonis seedling selection as the female, or seed, parent identified as 'F0264-2' (not patented). This pollination took place in Enkhuizen, Netherlands in 2004.
The new Osteospermum was discovered and selected as a single flowering plant within the progeny of the stated population grown in Enkhuizen, The Netherlands in 2005. The new Osteospermum plant has been repeatably asexually reproduced by cuttings in Enkhuizen, The Netherlands since 2005. The distinctive characteristics of this new Osteospermum plant are stable and reproduced true to type in successive generations.


The present invention relates to an optical module which is capable of amplifying light to be amplified to high power and which has a structure for effectively reducing influences of damage to other optical parts, and heat generation. The optical module includes a fiber unit constituted by an optical coupler, an amplification optical fiber, and an absorption optical fiber. Each of the amplification optical fiber and the absorption optical fiber has a core, a first cladding, a second cladding, and a third cladding. Further, each of the fibers allows the light to be amplified to propagate in a single mode in each of the cores, and allows pumping light to propagate in a multimode in the core, the first cladding, and the second cladding. The core of the amplification optical fiber is doped with an amplification dopant for amplifying the light to be amplified. The second cladding of the absorption optical fiber is doped with an absorption dopant for absorbing the pumping light.

1. Field of the Invention
The present invention relates to an optical module and a processing method using the same.
2. Related Background Art
At present, processing technology using laser light is attracting much attention, and demand for laser light sources is increasing in various fields such as machining and medical treatment. In particular, among various laser light sources, a laser light source which is attracting special attention includes a fiber laser light source. An optical fiber which is doped with rare earth elements such as Yb, Er and Tm is used as an optical amplification medium, and therefore light to be amplified is amplified by pumping light and laser oscillation is produced using a resonator structure, thereby generating light having a high output. The advantages of the fiber laser light source are that, since the laser light is confined within the optical fiber, treatment is easy, and since heat radiation properties are good, a large-scale cooling installation is not required.
As an amplification optical fiber, a fiber having a refractive index profile of single-cladding type is used in some cases. This amplification optical fiber of single-cladding type has one core which is doped with a rare earth element, and one cladding which surrounds this core and has a refractive index lower than that of the core. Further, this amplification optical fiber allows the light to be amplified to propagate in a single mode in the core and also allows pumping light to propagate in the core. In the amplification optical fiber, the rare earth element is excited by the pumping light and stimulated emission is caused. At this time, the light to be amplified which propagates through the amplification optical fiber is amplified. The pumping light which is not absorbed by the amplification optical fiber transmits through the amplification optical fiber to the outside (hereinafter, the pumping light which transmits is referred to as transmitting pumping light).
Further, as an amplification optical fiber, an optical fiber having a refractive index profile of double-cladding type is preferably used. The amplification optical fiber of double-cladding type has a core which is doped with rare earth elements, an inner cladding which surrounds the core and has a refractive index lower than that of the core, and an outer cladding which surrounds the inner cladding and has a refractive index lower than that of the inner cladding. Further, the amplification optical fiber allows the light to be amplified to propagate in a single mode in the core and allows the pumping light to propagate in a multimode in the core and the inner cladding. When such an amplification optical fiber of double-cladding type is used, high power pumping light is allowed to propagate in the amplification optical fiber and the light to be amplified can be amplified with a high gain (high-power amplified light is obtained).


A system for the laser beam deflection for optical measuring systems includes an optical element for the deflection of an incident laser beam and a driving unit for generating a rotational movement between the optical element and the incident laser beam in order to deflect the laser beam in different successive directions. The optical element includes at least two segments for the deflection of the incident laser beam by one fixed deflection angle respectively. During the rotational movement, the laser beam successively impinges on the different segments. The optical element has a disk-shaped or ring-shaped design, and the segments are wedge-shaped with inclined surfaces. In the case of a method for the laser beam deflection, a laser beam impinging in an offset manner with respect to the axis of rotation is deflected during a time period by each segment into precisely one defined direction.

The invention relates to a system for the laser beam deflection for optical measuring systems.
Measuring systems operating by means of laser beams are used in various fields of technology. A special example of such optimal measuring systems are air data systems which detect and analyze the characteristics of the air at a certain distance in precisely defined measuring directions. For example, the speed of the air movement in all three space axes, the air temperature and the air pressure can be measured thereby, Air data systems can be provided, for example, in an airplane or helicopter, a landcraft, a satellite, or stationary on the ground, Such air data systems are particularly used in aviation For example, in an airplane such air data systems are used to detect turbulences and other important air parameters in time, and initiate corresponding controls.
In order to direct the laser beam in different space directions, for example, scanners are used in the known measuring systems, which scanners guide the laser beam along a circular path.
In the journal SPIE, Vol. 2956, February 1997, Page 76, a Doppler LIDAR is described in which the speed components of the air are measured by means of a pulsed laser beam and a scanning mechanism. By means of the scanning mechanism, the beam is guided over various measuring points.
In Applied Optics, Vol. 33, No. 27, Page 6467, 1994, a scanner for an air data measuring system is described in which a rotating mirror deflects a laser beam. By way of stationary mirrors, the deflected beam is guided to the outside through a window of the measuring system in order to detect the measuring data.
In British Patent Document GB 1 238 783, a system for the light beam deflection is described in which an incident light beam is deflected in different directions by a rotating disk.
Finally, International Patent Document WO 99/54082 shows a method for deflecting a laser beam for the machining of material in which a wedge-shaped plate is rotating in order to guide a laser beam impinging in the center in a circular path.
In the case of the known laser beam deflection systems for measuring systems, it is problematic that the pulse repetition frequencies are limited in the upward direction. The known systems are suitable only for continuous-wave lasers or for lasers with low pulse repetition rates because the possible pulse frequency depends from the scanning rate. In addition, a synchronizing or triggering of each laser pulse is required. Moreover, the optical losses are to be kept as low as possible, and simultaneously high power densities should be present.
It is an object of the invention to provide a system and a method for the laser beam deflection for optical measuring systems which are suitable for the operation with extremely high-power lasers, such as pulsed lasers with high power and energy densities as well as high pulse repetition rates, and furthermore have low optical losses.
This object is achieved by means of a system for the laser beam deflection for optical measuring systems and by a method for the laser beam deflection in an optical measuring system. Additional advantageous characteristics, aspects and details of the invention are indicated in the dependent claims, the description and the drawings.
The system according to the invention for the laser beam deflection comprises, for example, an,optical element for the deflection of an incident laser beam and a driving unit for generating a rotational movement between the optical element and the incident laser beam in order to deflect the laser beam in different successive directions, the optical element comprising at least two segments for deflecting the incident laser beam by in each case a fixed deflection angle and, during the rotational movement, the laser beam successively impinging on the at least two segments.
The system according to the invention advantageously comprises a rotatable deflection unit which is connected in the beam direction in front of the optical element and is coupled to the driving element in order to move the laser beam before the impinging on the optical element into a circular path with a parallel beam axis. Accordingly, the rotational movement between the optical element and the impinging laser beam is generated by the rotating movement of the deflection unit. The optical element is preferably constructed to be stationary or fixed.
This has the effect that, during a defined time period, exactly the same deflection angle is always supplied in space and no angular movement takes place during this time. In other words, during the time period in which the laser beam impinges on a segment, the direction of the deflected laser beam is constant in space. When the laser beam impinges on the next segment, a change of direction of the deflected laser beam takes place, the new direction in space again being constant, while the laser beam is deflected by the corresponding segment. This is explained by the fact that, when sweeping over a segment, the laser beam always has the same angle of incidence onto the segment surface. The angle of emergence therefore also remains constant in the case of this segment.
As a result, particularly a high pulse rate can be achieved during the measurement, i.e., pulsed lasers can be used with arbitrarily high pulse repetition rates. Thus, extremely high-power lasers, such as pulsed lasers with high power and energy densities, can be used in optical measuring systems. Furthermore, a very high efficiency is achieved since the optical losses by means of the system according to the invention are extremely low. Additionally, a very high accuracy and stability of direction of the deflected laser beam, as well as a considerable temperature independence, is obtained. The system according to the invention can therefore have a very sturdy construction with respect to vibrations, shocks and accelerations. In addition, the system according to the invention is very compact with a low volume, which is particularly advantageous for applications in aviation and space travel.
The system according to the invention can be implemented almost without wear or with a long service life of the bearings, and consists of only a few components, making it particularly cost-effective.
Furthermore, by means of only one laser, several measuring positions, whose number is, for example, between 2 and approximately 100, can be detected almost isochronously. In this case, the scanning frequency of the individual measuring positions can be several hundred hertz. Idle times, during which the unit is interrupted because of switching operations, are avoided.
The optical element is advantageously arranged such that the incident laser beam carries out a circular path during the rotational movement on the surface of the optical element.
The optical element preferably has a disk-shaped or ring-shaped design, and the individual segments of the optical element preferably have a wedge-shaped construction, the wedge angle of each segment defining its deflection angle.
The segments of the optical element advantageously have surfaces which are inclined with respect to the beam axis of the incident laser beam, the angles of inclination of the surface of each segment together with the refractive index of the optical material defining its deflection angle. In particular, during the impinging of the laser beam onto a segment, the deflected laser beam maintains a constant direction in space.
Preferably, the segments are designed such that the incident laser beam is deflected toward the axis of rotation or the axis of symmetry. As a result, the window from which the laser beam emerges in the case of a corresponding optical measuring system, can be kept particularly small. However, it is also conceivable that the segments deflect the incident laser beam away from the axis of rotation.
For example, the segments are designed such that the respective incident laser is deflected into a different defined direction by each segment. However, several segments may also have identical designs in order to, during the rotational movement, deflect the laser beam several times into one and the same defined direction.
A transition area advantageously exists between the two adjoining segments, The transition are permits a change of direction of the laser beam without any beam interruption. As a result, a fading-over from one measuring point or one measuring direction to another measuring point or another measuring direction can take place during the measuring.
It is particularly advantageous for the optical element to have a spherical or aspherical construction on one side, for example, on the rear side, or to have a spherically or aspherically constructed surface element with a positive focal length. As a result, a displacement of the laser beam incident on the optical element during the circular-path movement of the laser beam at a desired measuring point can be corrected, so that the measuring position can be maintained particularly precisely.
The optical element is preferably flattened or constructed as a plane surface in a partial area which is not utilized for the beam deflection, or it has a recess in the partial area. As a result, a further weight reduction and miniaturization of the system can be achieved.
The optical element is preferably transparent, the respective deflection angle being generated by optical refraction in segments. However, it is also conceivable to develop the optical element in a reflecting manner, the respective deflection angle being generated by reflection on the segments or segment surfaces.
The dwell time of the deflected laser beam in a defined space direction can be determined as a function of the angular range of the respective segment and of the rotation frequency. This results in a particularly high flexibility with respect to the manner of measuring.
The segments preferably have a spherical or aspherical surface on one side. As a result a correction of a parallel beam displacement can be achieved.
The segments are preferably designed such that the beam deflection takes place toward the axis of rotation. The outlet hole for the laser beam can therefore be kept particularly small.
Advantageously, the optical element according to the invention is provided or can be used in a system for the laser beam deflection according to the invention. Advantages and characteristics of the optical element according to the invention also apply to the laser beam deflection system according to the invention.
According to another aspect of the invention, a method is disclosed for the laser beam deflection, by which an incident laser beam is successively deflected in at least two different directions by an optical element, in which case a deflecting unit rotates which is connected in front, and the laser beam impinging in a displaced manner with respect to the axis of rotation during a rotation in each case for a time period t impinges on at least two segments of the optical element, and each segment deflects the laser beam during the time period t into exactly one defined direction.
By means of the method according to the invention, particularly extremely high-power lasers or pulsed lasers with arbitrarily high pulse repetition rates can be used in optical measuring systems, and the scanning frequency of the individual measuring positions can, for example, amount to several hundred hertz. In addition, the advantages and characteristics which are indicated with respect to the system according to the invention and to the optical element according to the invention also apply to the method according to the invention.
Advantageously, the method is implemented by means of a system according to the invention.
In the following, the invention will be described as an example by means of the figures.

System and method for the laser beam deflection for optical measuring systems


Systems and methods for updating firmware or other critical configuration data in scalable distributed systems are provided. Such systems and methods can include (1) a master controller receiving (a) a firmware update file that is divided into a plurality of packets and (b) a metadata file that is associated with the firmware update file and (2) a first one of a plurality of slave controllers receiving the metadata file and, responsive thereto, updating a local peer table to include entries for the master controller and a group of the plurality of slave controllers that are available to share any of the plurality of packets and downloading each of the plurality of packets from a combination of the master controller and the group of the plurality of slave controllers.

Known systems and methods for updating firmware for control panels and sensors download an entire firmware file from a single source. For example, known systems and methods can include multiple ones of the control panels and sensors downloading firmware files from a local or cloud server and the local or cloud server transmitting full versions of the firmware files to requesting ones of the control panels and sensors. However, such known systems and methods require high bandwidth connections, take a long time to propagate the firmware files, and/or lack robust protection from network failures.
In view of the above, there is a continuing, ongoing need for improved systems and methods.

Systems and methods for updating firmware and critical configuration data to scalable distributed systems using a peer to peer protocol


A data transfer apparatus controls a data transfer speed between a transmitter and a receiver operating asynchronously of each other. The apparatus includes a data buffer for buffering data from the transmitter and an address register for indexing the data buffer. The apparatus further includes a stage register for indicating operation phases of data transfer to the receiver. The address register is updated when the stage register holds a predetermined value.

The present invention relates to a data transfer apparatus, and more particularly to a data transfer apparatus which controls a data transfer speed between a transmitter and a receiver operating asynchronously of each other.
In a conventional data transfer scheme, the transmitter checks an acknowledge signal from the receiver to ensure a completion of a data transfer. When the speed of the receiver is lower than that of the transmitter, the transmitter temporarily stops sending the subsequent data until the receiver has completed the data reception, so that the data transfer is made at discrete time intervals.
This conventional data transfer scheme has such a problem that the transmitter must check the acknowledge signal from the receiver at each time of completion of a data transfer. Therefore, the data cannot be transferred at high speed.

Data transfer apparatus for transferring data fixedly in predetermined time interval without a transmitter checking a signal from a receiver


There is provided an improved coiled tubing injector for injecting and withdrawing a length of flexible, cylindrical tubing into and from a well bore. The improved injector comprises first and second sets of gripper shoes, and drive mechanism for moving the sets of gripper shoes around first and second endless paths, respectively. The endless paths include parallel sections disposed on opposite sides of a length of the tubing. Within these parallel sections, the gripper shoes are pressed against the tubing with sufficient force to hold the tubing therebetween. Each gripper shoe includes a base portion connected to the drive mechanism and at least two substantially nondeformable gripper elements, each having cylindrical gripping surfaces corresponding to the outer surface of the tubing. A body of elastomeric material connects the gripper elements to the base portion and permits movement of the gripper elements between open and closed positions.

The present invention relates to an apparatus for handling a continuous length of coiled tubing for insertion into or removal from a well bore, such apparatus is commonly referred to in the art as a coiled tubing injector.
Coiled tubing injectors of the type described in U.S. Pat. No. 4,585,061 were originally used during workover operations to inject a relatively small diameter, continuous length of coiled tubing into a well bore while the well was under pressure. In such a case, the tubing must be literally forced or "injected" into the well through a sliding seal to overcome the well pressure until the weight of the tubing exceeds the force produced by the pressure acting against the cross-sectional area of the tubing. Thereafter, the weight of the tubing has to be supported by the injector. The process is reversed as the tubing is removed from the well. In recent years, the coiled tubing has been used in combination with a mud turbine motor to drill original bores, has been used as the permanent tubing in production wells, and continues to be used in various workover and service applications. Because of the advantages of continuous coiled tubing, and the resulting new uses, the state of the art of manufacturing coiled tubing has rapidly progressed until tubing is almost three inches in diameter. These large tubings have a wall thickness and sufficient tinsel strength to support up to 20,000 feet hanging in a well bore.
The only method by which a continuous length of tubing can be either forced against pressure into the well, or supported while hanging in the well bore, while lowered or raised is by continuously gripping the tubing along its length. This is achieved by arranging continuous chain loops on opposite sides of the tubing with active reaches extending parallel to the tubing just before it enters the well bore. The continuous chains carry a series of gripper shoes which are pressed against opposite sides of the tubing and grip the tubing.
In order to handle progressively larger, longer, and heavier tubing, the gripping force must be progressively increased. This can be achieved by increasing the force pressing the gripper shoes against the tubing, by increasing the number of gripper shoes by increasing the length of the chains, by increasing the contact area of the gripper shoe, or by improving the gripping surfaces.
As the length of the chain increases, the tolerance problems to insure that all of the individual grippers are contacting the tubing with equal force presents a practical limitation, which has been reached with current designs. The application of greater force to press the grippers against the tubing, is an even more clear limitation because this will deform. Current grippers are already surfaced with carbide grit which penetrates the surface of the tubing to the point of damaging the tubing. The use of carbide surface treatment is relatively extensive and the expensive chain must be replaced frequently because when the grit wears smooth, the grippers can no longer effectively handle the tubing. The grippers can encircle only a limited percentage of the circumference of the tubing because the grippers must engage and disengage from the tubing at the beginning and end of the active reaches of the chains, and any attempts to increase the circumferential contact has resulted in unacceptable marring of the surface of the tubing to the point of causing the tubing to fail. Any increase in the force applied to the gripper results in unsatisfactory deformation of the tubing, typically causing it to become permanently egg-shaped. All of these design variables have reached the practical limits using current designs for moderately sized tubing, and the larger tubing cannot be satisfactorily handled, except in relatively shorter lengths, with even larger and longer tubing presently being demonstrated.


The invention concerns a hydraulic valve (1) that comprises an electromagnet (2) having an armature (3), and a valve part (4) having at least two valve seats (5, 6). The electromagnet (2) is formed by a hollow cylindrical plastic coil spool (8), a coil winding (10) received in the coil spool (8) and a magnet housing (11) surrounding the coil winding (10), the hollow cylinder of the coil spool (8) being configured as an armature space (14) for the armature (3), into which armature space (14) an upper pole (15) and a lower pole (16) of the electromagnet (2) extend. The valve part (4) is formed by a hollow cylindrical valve housing (18) that comprises a pressure delivery connection (P) on one front end, as well as a load connection (A) and a tank connection (T) arranged on its peripheral surface and, pressed into its hollow cylinder, two cup-shaped deep-drawn parts (23, 24) comprising the valve seats (5, 6). The hydraulic valve (1) can be inserted with the valve part (4) into a complementary valve reception and comprises a fixing flange (26) through which it can be screwed, pressure-medium tight, on the valve reception. In the invention, at least the valve housing (18) of the valve part (4) and/or the lower pole (16) of the electromagnet (2) is configured as a separate part that can be made without chip removal, and the lower pole (16) is made integrally in one piece with the fixing flange (26) of the hydraulic valve (1) and also serves as a reception socket for the valve housing (18).

DE 199 084 40 A1 discloses an electromagnetic hydraulic valve of a generic type that is configured as a 3/2 directional switching valve and generally comprises an electromagnet with an axially movable armature and a valve part with at least two valve seats and a closing ball that corresponds to at least one valve seat. The electromagnet is formed by a hollow cylindrical plastic coil spool with an electric plug contact, at least one coil winding received in the coil spool and a magnet housing surrounding the coil winding, the hollow cylinder of the plastic coil spool being configured at least partially as an armature space for the armature, which armature space is lined with a non-magnetic metal sleeve. The magnet housing of the electromagnet, in contrast, is configured as a cylinder tube sleeve whose one front end is angled into the interior of the sleeve to form a circular ring-shaped bottom and whose other front end comprises a plurality of turn-over tabs through which the magnet housing is connected to the plastic coil spool that can be inserted into the magnet housing. Further, a metal disk cast into the plastic coil spool and a pole core inserted into the hollow cylinder of the coil spool form an upper pole of the electromagnet, while its lower pole is formed by an extension of the valve part of the hydraulic valve, which extension can be inserted into the hollow cylinder of the coil spool and is conductively connected to the magnet housing through the bottom thereof. The valve part substantially comprises a hollow cylindrical valve housing that has a pressure delivery connection on one front end, as also a load connection and a tank connection that are made as radial holes in the cylinder jacket of the valve housing. Inside the hollow cylinder of the valve housing is arranged respectively between the pressure delivery connection and the load connection, and between the load connection and the tank connection, one of the valve seats of the valve part. Both valve seats are made as axial apertures in the bottoms of two cup-shaped deep-drawn parts that are fixed with their peripheral surfaces in the hollow cylinder of the valve housing and are connected to each other by a plastic sleeve. The loosely arranged closing ball of the valve part, that is operatively connected to the armature of the electromagnet through a tappet, is guided in this plastic sleeve. Through a compression spring arranged between the electromagnet and the pole core of the upper pole, the armature exerts, in a non-energized state of the electromagnet, a constant biasing force on the closing ball for closing the pressure delivery connection of the hydraulic valve. This hydraulic valve, thus configured as a magnetic pull valve, can be inserted with the valve part that comprises a plurality of outer sealing rings into a complementary valve reception. The hydraulic valve comprises a separate fixing flange which is arranged between the electromagnet and the valve part and through which the hydraulic valve can be screwed, pressure-medium tight, on the valve reception.
A drawback of this prior art electromagnetic hydraulic valve, however, is that it is composed of a relatively large number of separate parts some of which, for example the magnet housing and the valve seats, can certainly be made without chip removal. Other parts, however, like the valve housing of the valve part, as also the armature and the pole core of the upper pole of the electromagnet, have a relatively solid configuration and, due to their structural design, can only be fabricated by machining methods. However, due to the relatively long machine cycle times, the tools and equipment required and the material used, fabrication by machining methods causes considerable costs and, in the last analysis, has proved to be uneconomic. In addition, due to the large number of individual parts, the work and expense involved in the final assembly of the hydraulic valve are also increased so that, on the whole, the manufacturing costs of this prior art hydraulic valve can be expected to be disadvantageous.

Electromagnetic hydraulic valve, typically a 3/2 directional switching valve for controlling a variable valve train of an internal combustion engine


This disclosure relates to a method, article of manufacture, and apparatus for finding a shortest path in a cloud. In some embodiments, this includes obtaining one or more nodes associated with a tenant, obtaining hop counts for each of the one or more nodes, determining a threshold hop count based on the hop counts, identifying one or more local nodes based on the threshold hop count, and associating the one or more local nodes with the tenant.

Cloud computing allows users to perform computing tasks where data, applications and other computing systems resources are accessed over a network. The network of servers and connections used to provide the computing service is generally referred to as the cloud. That is, cloud service providers typically abstract the underlying resources and infrastructures used to deliver the service, so that users can access the resources somewhere in the cloud. Without worrying about the logistics, such as where files are located or how files are stored on dedicated physical storage devices, users can often realize substantial cost savings.
In a cloud system, one service provider may provide files to multiple customers on a global basis. Sharing of computational resources in a cloud system enables a provider to use resources efficiently. Multi-tenant architectures have been developed to allow multiple user groups (also referred to as "organizations" or "tenants") to share the computational resources in cloud computing.
Stronger than simple access control, tenancy is a logical compartmentalization of data and resources within the cloud. Each tenant appears to have unique and sole access to a subset of the system resources. A tenant may be further configured to contain multiple subtenants. Associated with a tenant may be specific access nodes, security control, storage policies, and access to the data stored on that tenant's resources.
During a multi-tenancy configuration, administrators may add certain access nodes as resources available to tenants. Since a tenant is a conceptual subset of the computational resources within a cloud, an administrator may not be aware of the physical location and the logical configuration of an access node. In many instances, a cloud system may comprise distributed computational resources serving customers on a global basis. These computational resources may in turn contain computational resources located across multiple data centers in different locations. Thus, without knowing the underlining network layout of the access nodes available to a tenant, an administrator's configuration may not provide efficient routes to reach resources serving the customers.
There is a need, therefore, for an improved method or system that would find shortest path in multi-access nodes to improve the efficiency and reduce the latency of cloud service networks.

Finding shortest path in multi-access nodes in cloud service


The following describes an apparatus for and method of providing and supporting distributed call handling over a plurality of network nodes (401, 403, 405, 407, 409, 411, 413) in a communication system, wherein the network nodes (401, 403, 405, 407, 409, 411, 413) are found in each device with the system, rather than only in the repeaters (101, 103, 105, 107, 109), the site controller (111), or the zone controller (ZC) for the system. The call establishment process is provided as elements (301, 303, 305, 307, 309, 311, 313) of a state machine. Each of the elements (301, 303, 305, 307, 309, 311, 313) is distributed over one or more of the plurality of network nodes (401, 403, 405, 407, 409, 411, 413). If one of the network nodes becomes unavailable, the element(s) supported by the now unavailable network node is reassigned (705, 809), as necessary.

The basic operation and structure of a land mobile radio system is well known. Land mobile radio systems typically comprise one or more radio communication units and one or more repeaters that transceive information via radio frequency (RF) communication resources. These communication resources may be narrow band frequency modulated channels, time division multiplex slots, frequency pairs, and so forth, which are sourced by a plurality of repeaters or base stations. Land mobile radio systems may be organized as trunked communication systems, where a plurality of communication resources is allocated amongst a group of users by assigning the repeaters on a communication-by-communication basis with an RF coverage area. In addition, calls made from RF communication units to landline telephones may also be placed through the use of switches connected to the PSTN (Public Switched Telephone Network) and the repeaters that source the RF communication resources.
Generally, trunked two-way RF communication systems provide mobile and portable communication units with wireless services similar to many wired communication networks. Such examples include full-duplex telephone voice communication, two-way mobile-to-mobile group dispatch communication, and two-way mobile-to-dispatcher group dispatch communication. A typical trunked communication system site, where each different site has a different physical location, is composed of a number of full-duplex repeaters, each coupled to a variety of devices to support interconnection to the public telephone network, mobile-to-mobile calling, and to one or more dispatcher console positions. These devices typically provide a centralized control for the repeaters. For example, a single central controller provides radio channel signalling encode and decode functions, authorization functions, resource determination functions, and communication activity logging A single telephone interconnect switch typically provides the repeaters with an interface to one or more telephone lines to support telephone interconnect communication. In systems employing a single device that is shared among the repeaters, a failure of the single device may render one or more of the desired services or functions inoperable, thus impairing communications in the system. Placing redundant devices within the system is expensive and an inefficient use of space and resources.
Accordingly, there is a need for a communication system that efficiently covers a large area while providing dynamic and flexible allocation of distributed call control functions. There is also a need for a communication system that provides recovery for failed network nodes.

Provision of distributed call handling over a plurality of network nodes


A display apparatus, that includes current driving type luminescent elements, has a driving system that takes the conduction types of TFTs to control the emission of the luminescent elements into consideration. In order to reduce driving voltage and improve display quality simultaneously, the arrangement is provided such that if the second TFT which performs the “on-off” function of the current for the luminescent element is of an N channel type, the potential of the common power supply line (“com”) is lowered below the potential of the opposite electrode (“op”) of the luminescent element to obtain a higher gate voltage (“Vgcur”). In this case, if the first TFT connected to the gate of the second TFT is of a P channel type, when using the potential of the potential-holding electrode (“st”) at the “on” state as a reference, potentials of the scanning signal (“Sgate”) at the lower potential and the common power supply line (“com”) are rendered of the same polarities with respect to this potential of the potential-holding electrode (“st”). Therefore, the potential of the image signal (“data”) to turn “on” can be shifted within the range of the driving voltage in the display apparatus in the direction to reduce resistances at the “on” states of the first TFT and the second TFT to reduce driving voltage and improve display quality.

1. Field of the Invention
The present invention relates to an active matrix type display apparatus including luminescent elements such as EL (Electro-luminescence) elements or LED (Light Emitting Diode) elements which emit light by driving current flowing in thin films of organic semiconductors or the like, and also including thin film transistors (hereinafter TFT's) to control the emitting operation of these luminescent elements. More particularly, the present invention relates to a technique of driving each element formed in this type of display apparatus.
2. Description of the Related Art
Active matrix type display apparatuses incorporating luminescent elements of a current controlling type, such as EL elements and LED elements, have been proposed. Since any luminescent element employed in this type of display apparatus emits by itself, there are advantages in using no back-light and in having a minimal dependence on the viewing angle and the like.
FIG. 31 is a block diagram illustrating an active matrix type display apparatus incorporating organic thin film EL-elements of an electric charge filling type, as an example of these types of display apparatuses. In the display apparatus 1A shown in this figure, a plurality of scanning lines "gate", a plurality of data lines "sig" extending in a direction that intersects the direction in which the scanning line "gate" extend, a plurality of common power supply lines "com" extending parallel to the data lines "sig", and a plurality of pixels 7 located at the intersections of the data lines "sig" and the scanning lines "gate" which are formed on a transparent substrate.
Each pixel 7 comprises a first TFT 20 in which a scanning signal is supplied to the gate electrode (a first gate electrode) through the scanning gate, a holding capacitor "cap" which holds an image signal supplied from the data line "sig" via the first TFT 20, a second TFT 30 in which the image signal held by the holding capacitor "cap" is supplied to the gate electrode (a second gate electrode), and an luminescent element 40 (indicated as a resistor) into which the driving current flows from the common power supply line "com" when the element 40 is electrically connected to the common power supply line "com" through the second TFT 30.
In the above display apparatus 1A, both the first TFT 20 and the second TFT 30 are conventionally formed, as with an N channel type TFT or a P channel type TFT, as shown in an equivalent circuit diagram of FIG. 32, from the viewpoint of simplifying the production process, for example, in the case of an N channel type. Taking the N channel type as an example, as shown in FIGS. 33(A) and (B), when the high potential image signal "data" is written into the holding capacitor "cap" from the data line "sig", while the scanning signal "Sgate" supplied through the scanning line "gate" has become higher in potential to turn the first TFT 20 "on", the second TFT 30 is held in the "on" state. Consequently, in the luminescent element 40, the driving current keeps flowing from a pixel electrode 41 to an opposite electrode "op" in the direction indicated by the arrow "E" and consequently, the luminescent element 40 keeps emitting (the "on" state). On the other hand, when the image signal "data", which is lower than the intermediate between the potential of the common power supply line "com" and the potential of the opposite electrode "op", is written into the holding capacitor "cap" from the data line "sig", while the scanning signal "Sgate" supplied through the scanning line "gate" has become higher in its potential to turn the first TFT 20 "on", the second TFT 30 is turned "off" and consequently, the luminescent element 40 is turned "off" (the "off" state).
In the above display apparatus 1A, a semiconductor thin film, an insulating thin film, an electrode, etc., which constitute each element, are formed by thin films deposited on the substrate. Considering the heat resistance of the substrate, a low-temperature process is often used to form the thin films. Therefore the quality of the thin film is poor, as is evidenced by the frequent defects caused by a physical-property difference between a thin film and a bulk, which result in problems such as an electrical breakdown, and wherein time-degradation is apt to arise in the TFT and similar devices.
In the case of a liquid crystal display apparatus incorporating liquid crystals as light modulation elements, although it also uses the thin films, time-degradation can be suppressed not only in the liquid crystal but also in the TFT, because the light modulation element is driven by AC power. On the other hand, in the display apparatus 1A incorporating luminescent elements of the current controlling type, time-degradation is more often encountered in the TFT than in the liquid crystal display apparatus insofar as the apparatus is essentially driven by D.C. power. Although improvements have been made in the structure of the TFT and the process techniques in the display apparatus 1A, incorporating luminescent elements of the current controlling type, they do not yet seem to be improved enough.
In the case of incorporating the liquid crystals as the light modulation elements, the power consumption is small because the light modulation element is controlled by the voltage which causes the current flow in each element to be only momentary. On the other hand, in the display apparatus 1A incorporating luminescent elements of the current controlling type, a constant driving current is required to keep the luminescent element "on", and this results in high power consumption and the risk of the frequent occurrence of electrical breakdown and time-degradation.
Further, in the liquid crystal display apparatus, the liquid crystal can be AC-driven by one TFT per one pixel. On the other hand, in the display apparatus 1A incorporating luminescent elements of the current controlling type, the luminescent element 40 is DC-driven by two TFTs 20, 30 per one pixel. This raises the driving voltage, and exacerbates the aforementioned problems, such as electrical breakdown and time-degradation. For example, as shown in FIG. 33(A), the gate voltage "Vgsw" of the first TFT, when selecting a pixel, corresponds to the potential difference between the potential equals to the higher potential of the scanning signal "Sgate" and the potential of the potential-holding electrode "st" (the potential of the holding capacitor "cap" or the potential of the gate electrode of the second TFT 30). Therefore when the potential of the potential-holding electrode "st" and, hence, the gate voltage "Vgcur" of the second TFT 30 are raised to make the luminescent element 40 emit in a high luminance, the gate voltage "Vgsw" of the first TFT 20 is lowered correspondingly. Therefore, the greater amplitude of the scanning signal "Sgate" has to be employed, requiring the higher driving voltage in the display apparatus 1A. Besides, in the aforementioned display apparatus 1A, since when the luminescent element 40 is "off", the potential of the image signal "data" is made lower than the intermediate potential between the potential of the common power supply line "com" and the potential of the opposite electrode "op" in order to turn the second TFT 30 "off", there is another problem of increased amplitude of the image signal "data". Accordingly, in this display apparatus 1A, special consideration for the power consumption and the withstanding of voltage of the TFT, etc. is needed compared to the liquid crystal display apparatus. However, the conventional display apparatus 1A has not been provided with the sufficient consideration of these factors.


This invention provides a microfluidic device for use in the detection of one or more analytes in a fluid using solid-phase affinity binding assays. The device offers a practical, easy-to-use, portable, inexpensive, robust analytical system for the parallel and quantitative detection of multiple analytes. In addition, this invention provides methods and devices for the formation of concentration gradients of capture molecules immobilized on a solid phase.

Solid phase affinity binding assays remain among the most versatile and rapid methods for detection of chemical and biological analytes from fluid samples. However, field deployment and point-of-care use of these diagnostic assays have historically been impractical because of the cost of instrumentation and test devices, complicated operation parameters and protocols, and lack of methods for robust storage of biological reagents, the degradation of which leads to poor assay performance.
Microfluidic systems offer solutions to many of these problems. Microfluidic systems and methods of use have been described in detail (Verpoorte, E., Electrophoresis, 2002 23(5), 677-712; Lichtenberg, J., et al., Talanta, 2002. 56(2),233-266; Beebe, D.J., et al., Annual Review of Biomedical Engineering, 2002,4, 261-286; Wang, J., Electrophoresis, 2002, 23(5), 713-718; Becker, H. and L.E. Locascio, Talanta, 2002, 56(2), 267-287; Chovan, T. and A. Guttman, Trends in Biotechnology, 2002. 20(3), 116-122; Becker, H. and C. Gartner, Electrophoresis, 2000, 21(1), 12-26; McDonald, J.C., et al., Electrophoresis, 2000, 21(1), 27-40; Weigl, B.H. and P. Yager, Science, 1999, 283, 346-347; and Shoji, S., Topics in Current Chemistry 1998, 194:163-188; U.S. Pat. Nos. 5,932,100; 5,922,210; 5,747,349; 5,972,710; 5,748,827; 5,726,751; 5,726,404; 5,716,852; 6,159,739; 5,971,158; 5,974,867; 6,007,775; 6,221,677; 5,948,684; 6,067,157; 6,482,306; 6,408,884; 6,415,821; and U.S. Patent Application Nos. 09/703,764 filed Nov. 11, 2000; 09/724,308, filed Nov. 28, 2000; 09/675,550, filed Sep. 27, 2000; 09/863,835, filed May 22, 2001; 09/428,839, filed Oct. 28, 1999; 09/723,823, filed Nov. 28, 2000; 09/503,563, filed Feb. 14, 2000; 09/574,797, filed May 19, 2000; 09/579,666, filed May 26, 2000; and 09/956,467, filed Sep. 18, 2001; all of which are incorporated herein in their entirety to the extent not inconsistent herewith).
Microfluidic systems for use in analyte detection in fluid streams have been studied extensively (e.g. U.S. Pat. Nos. 5,747,349; 5,716,852; 6,007,775; 5,984,684; and U.S. Patent Application No. 09/503,563 filed Feb. 14, 2000; Ser. No. 09/574,797, filed May 19, 2000; Ser. No. 09/863,835, filed May 22, 2000; and Ser. No. 09/724,308, filed Nov. 28, 2000). One fluid-phase analyte detection system utilizes methods for the solid-state storage and preservation of assay reagents in a microfluidic device, negating the need for multiple reagent sources external to the detection device (U.S. Pat. No. 6,007,775, incorporated herein in its entirety, to the extent not inconsistent herewith). Methods and devices for the electrokinetic control or transport of molecules in a microfluidic channel using electrophoresis, isoelectric focusing, and transverse electrophoresis have also been studied (e.g. Harrison, D. J., et al., Sensors and Actuators B: Chemical, 10(2), 107-116; and U.S. Patent Application No. 09/579,666 filed May 26, 2000).
Design of microfluidic systems using laminate technology allows multichannel analysis and the formation of 3-dimensional microfluidic systems of varying degrees of complexity (Jandik, P. et al. Journal of Chromatography A, 2002, 954: 33-40; Cabrera, C. (2002) "Microfluidic Electrochemical Flow Cells: Design, Fabrication, and Characterization", Thesis, 2002 Department of Bioengineering. Seattle, University of Washington; Cabrera, C. R., et al. Analytical Chemistry, 2001, 73(3), 658-666; Holl, M., et at., "Design of a Microfluidic Electrochemical Flow Cell", Electrophoresis, 2000 (submitted); Holl, M. R., et al., "Microfluidic device and methods for continuous-flow transverse electrokinetic separations", Electrophoresis (submitted); Yager, P., et al., "Design of Microfluidic Sample Preconditioning Systems for Detection of Biological Agents in Environmental Samples", SPIE, Santa Clara, CA; Yager, P., et al., "Analytical Devices Based on Transverse Transport in Microchannels"; Micro Total Analysis Systems 2000, University of Twente, the Netherlands, Kluwer Academic Publishers; Anderson; McDonald, J.C. and Whitesides, G.M., Accounts of Chemical Research, 35(7), 491-499; and McDonald, J.C., et at., Electrophoresis, 21, 27-40; all of which are incorporated herein in their entirety, to the extent not inconsistent herewith).
Solid phase microfluidic affinity binding assays have also been explored for their use with surface plasmon resonance (SPR) technologies to detect analyte binding within a microfluidic device (Jung, L. S., et al. Sensors and Actuators, 1999, 54,137-144; Lyon, L.A., et al. Sensors and Actuators B, 1999, 54, 118-124; Naimushin, A. N., et al., "Detection of Staphylococcus Aureus Enterotoxin B at Femtomolar Levels with a Miniature Integrated Two-channel Surface Plasmon Resonance (SPR) Sensor", Biosensors & Bioelectronics, 2002, 17:573-584; Place, J. F., et at., Biosensors, 1985, 1, 321-353, all of which are incorporated herein in their entirety to the extent not inconsistent herewith). Other SPR sensing devices have also been described for single or multiple analyte detection (U.S. Pat. Nos. 5,815,278; 5,822,073; 5,991,048; 5,858,799; and U.S. Patent Application Nos. 09/566,772 filed May 8, 2000; 60/1 32,893 filed May 6,1999; 60/1 32,895 filed May 6,1999; and 60/132,894 filed May 6,1999, all of which are incorporated herein in their entirety to the extent not inconsistent herewith).
It is often desirable to detect multiple analytes in parallel in a solid phase affinity binding assay. This parallel detection often involves complex protocols for the deposition and/or patterning of capture molecules on the binding surface. Such assays often require extensive development efforts for determining, for example, the optimum concentration of capture molecules bound to the solid phase.
There is a long felt need in the art of biological and chemical assays for a simple, easy-to-use, practical, inexpensive, compact, portable, versatile, and inexpensive device for performing quantitative bioassays in a variety of testing conditions, from controlled hospital and clinical environments to the often-extreme environments experienced by armed-forces personnel. Ideally, such devices perform parallel analysis of multiple analytes and require minimal development effort for determining optimal assay parameters.

Microfluidic device and surface decoration process for solid phase affinity binding assays


A laser driving circuit configured to drive a semiconductor laser diode, which is less susceptible to noise interference and capable of achieving the control of laser light intensity with high accuracy. Respective circuit components in the laser driving circuit such as an amplifier circuit, a sample hold circuit, a voltage-to-current converter, and a switching circuit are all integrated into an integrated circuit. A capacitor included in the sample hold circuit is further provided as built-in in the integrated circuit, which is previously attached externally. In addition, by changing the resistance of a resistor which is externally connected between the bias current setting terminal of the amplifier circuit and the ground potential by way of a terminal of the integrated circuit, the current outputting capability of the amplifier circuit can be variably adjusted through the adjustment of the charging time of the capacitor. As a result, the response speed of a feedback control loop for controlling the light intensity of laser diode can be increased with less noise interference and high accuracy.

A variety of semiconductor laser driving circuits are known previously by including one illustrated in FIG. 5 for controlling the intensity of light emitted from a laser diode used in an image-forming apparatus. (Japanese Patent No. 3332916, for example.)
Referring to FIG. 5, a semiconductor laser driving circuit 100 is configured to drive a laser diode LD such that the intensity of light emitted therefrom reaches a predetermined value.
The semiconductor laser driving circuit 100 includes at least a photodiode PD, an amplifier circuit 102, a sample hold circuit 103, a current generator 104, an on-off circuit 105, a detection circuit 106, and resistors R101 and R103.
The amplifier circuit 102, sample hold circuit 103, current generator 104, on-off circuit 105, and detection circuit 106 are all integrated into one single integrated circuit (IC).
In the amplifier circuit 102, an external signal Sext is inputted to the non-inverting terminal and an output signal from the detection circuit 106 is inputted to the inverting terminal. In addition, an output signal from the amplifier circuit 102 is outputted to the sample hold circuit 103.
The anode of the photodiode PD is connected to the input terminal of the detection circuit 106 and a photocurrent generated by the photodiode PD is inputted to the input terminal.
The output terminal of the detection circuit 106 is connected to the non-inverting terminal of the amplifier circuit 102, and to the R101 which operates to convert the photocurrent into a voltage.
In addition, the sample hold circuit 103 consists of an analog switch AS and a capacitor HC, and a sample hold signal Ssh is inputted to the control electrode of the analog switch AS.
The sample hold signal Ssh is configured to turn on the analog switch AS to be electrically continuous, only when the on-off circuit 105 is switched on by an image signal Sp.
When the analog switch AS is turned on, the capacitor HC is charged by the output voltage from the amplifier circuit 102.
In contrast, when the analog switch AS is turned off, the capacitor HC is charged by the output voltage from the amplifier circuit 102 to be held as a charged voltage of the capacitor HC.
The current generator 104 is configured to generate a current to be proportional to a sample-held voltage, or the voltage caused by the charge in the capacitor HC. This current serves as a driving current for the laser diode LD.
The constant for the proportionality of current-to-voltage conversion is determined by the resistor 103 which is connected between the terminal 123 and the ground.
The switching circuit 6 is configured to be on-off controlled according to the inputted image signal Sp so as to intermittently supply the current outputted from the current generator 104 to the laser diode.
Therefore, in the semiconductor laser driving circuit 100 previously known, the capacitor HC for the sample hold circuit 103 is externally provided and the response time for light intensity control in the feedback control loop is adjusted by suitably selecting the capacitance value for the capacitor HC Japanese Patent No. 3332916).
Because of the capacitor HC externally connected to IC, a difficulty encountered in the previous laser driving circuit is that the point of grounding IC cannot be placed in close vicinity of that of the capacitor HC, and that, as a result, a slight difference in ground potential arises due to the current flowing through grounded circuits from one grounding point to another, which may be notable particularly in the laser driving circuit dealing with pulse currents.
In addition, considerable noises tend to be generated both inside and outside IC. The IC terminals, to which external devices are connected, may be affected by various interferences with relative ease through parasitic capacitances derived between groundings, power sources, and signal conductors.
As a result, driving currents for the laser diode unduly fluctuate and the control of light intensity cannot be carried out with satisfactory accuracy in the previous laser driving circuit.
It is therefore desirable to provide a semiconductor laser driving circuit having improved capability of controlling laser light intensity with satisfactory accuracy.

Semiconductor laser driving circuit less susceptible to noise interference


The present invention provides a wide-area sample-based reader design which serves as a diagnostic detection device for bio-particles.

The diagnostic detection devices currently available in the market are primarily based on exciting a spot of the sample and reading the emission from the same spot (FIG. 1). The spot is usually a 1 mm×1 mm area. The sample is generally contained in a vial (as in spectrophotometers using cuvettes), a transparent capillary through which the sample is flowing, or a lateral flow cartridge. In this mode of detection, the emission signal is based on the concentration of the target particle in the spot that is excited. For very low concentration of target particle, this signal can be very small and sometimes lower than the dark current or background reading level, thus rendering the sample undetectable.
U.S. patent publication 2008/0149840 provides a fluorescent detector configured to detect polynucleotides using a microfluidic channel-based cartridge. In this invention, the microfluidic channel is usually closed to avoid evaporative losses as liquid quantities are much smaller, in the range of 0.1 μl to 900 μl. Thus, US2008/0149840 uses a spot imaging method where a small 1 mm or smaller diameter spot of the microfluidic channel is imaged. This invention is restricted to detection of nucleotides in a PCR based assay.
U.S. patent publication 2013/0230844 uses a lateral flow cartridge for detection of a fluorescent signal to detect the analyte. This again is a spot detection method with a spot size of 2.5 mm×0.8 mm, thus limiting the analyte size that is detected.
Keeping in view the requirement of increasing the emission signals, the applicant has designed a reader for diagnostic detection of bio-particles which is simple, effective for a wide range of sample volumes (100 μl-10 ml), economical and can be easily used in field set up (in the absence of hospitals or laboratories).

Wide-area-sample based reader design for diagnostic detection of bio-particles


A retardation arrangement for converting an input radiation beam, incident from an input side of the retardation arrangement, into an output radiation beam which has over its cross section a spatial distribution of polarization states which can be influenced by the retardation arrangement and differs from the spatial distribution of polarization states of the input radiation, is designed as a reflective retardation arrangement. A useful cross section of the retardation arrangement has a multiplicity of retardation zones of different retardation effect. Such a mirror arrangement having a retardation effect varying as a function of location can be used to compensate undesired fluctuations in the polarization state over the cross section of an input radiation beam and/or to set specific output polarization states, for example in order to set radial or tangential polarization.

The invention relates to a retardation arrangement for converting an input radiation beam, incident from an input side of the retardation arrangement, into an output radiation beam which has over its cross section a spatial distribution of polarization states which can be influenced by the retardation arrangement and differs from the spatial distribution of polarization states of the input radiation beam, and to a microlithography projection exposure machine having at least one such retardation arrangement.

Optically polarizing retardation arrangement, and a microlithography projection exposure machine


A spectrophotometric optical system of a microplate reader and a filter wheel thereof are disclosed. The filter wheel comprises a pivotable wheel body, at least one narrow-band filter with a relatively long central wavelength mounted to the wheel body, and at least one narrow-band filter with a relatively short central wavelength mounted to the wheel body. The narrow-band filter with a relatively long central wavelength is provided with a diaphragm on a front surface thereof The diaphragm is formed with a plurality of apertures. By the diaphragm attached to the front surface of the narrow-band filter with a relatively long central wavelength, an energy matching between light of longer wavelength and light of shorter wavelength may be achieved. Further, due to the uniformly distributed apertures in the diaphragm, an even light spot may be obtained.

In a spectrophotometric optical system of a microplate reader, an analog signal obtained by a photoelectric conversion should be ensured to match a range of an analog-to-digital converter (ADC) of a detection circuit. However, light of different wavelengths may carry substantively different amounts of energy. For example, an amount of energy carried by longer wavelength light might be 20 times as much as that carried by shorter wavelength light. Moreover, the light of different wavelengths share processing circuit modules, and these modules could not balance such an energy difference between lights of different wavelengths. Thus, some analog signals could not match with the range of the ADC, e.g. going beyond the limit of the range. In addition, a colorimetric element of a microplate reader generally has a plurality of colorimetric channels. In order to ensure a uniform output of the plurality of colorimetric channels, an even distributed light spot (i.e., energy of image) is required.
In order to solve the above-mentioned problems, the amounts of energy carried by light of various wavelengths in the light path shall be balanced so as to achieve substantively the same outputs. At this point, two kinds of methods might be used according to the prior art, which will be described hereinafter.
1) Adjust a gain value of an analog channel of the detection circuit rather than adjust an energy amount of the light, so as to realize an appropriate matching between the analog signal obtained via a photoelectric conversion and a range of the ADC of the detection circuit. However, as the gain value increases, a noise in the circuit also increases, thereby leading to a degraded detection accuracy.
2) Adjust energy amounts of the lights so that energy amounts of various wavelengths light are substantively the same, and thus it is no more necessary to greatly increase the gain value of the analog channel of the detection circuit. Accordingly, an excess noise due to a relatively larger gain value could be avoided and thus the detection accuracy may be improved.
For the above-mentioned latter method, the system could be incorporated with a cold mirror, an attenuator, an energy-matching type of optical filter, or a diaphragm with a center aperture. However, there are some shortcomings with any of the above-mentioned element, which will be described hereinafter.
I) For a technical solution of incorporating a cold mirror in the light path, the cold mirror will be positioned in 45 degrees with respect to an incidence light so as to turn the light travel path with 90 degrees. Thus, a suitable space room for accommodating the mirror should be designed. In addition, various parameters of the cold mirror need to be adjusted depending on a specific amount of energy carried by respective wavelength light. Accordingly, an increased cost and an enhanced failure risk will be caused.
II). For a technical solution of disposing an attenuator in front of an optical filter, the additional attenuator will notably increase a manufacture cost of the whole system.
III). For a technical solution of utilizing an energy-matching type of optical filter, it is problematic in that the process of applying a specific film to the optical filter is difficult, and moreover the optical filter with a relatively low light transmittance will has a relatively large failure risk.
IV). For a technical solution of incorporating a diaphragm with a center aperture, it is problematic in that the light spot is not even and a rim energy is low, and thus each fiber could not be assured to obtain an substantively equivalent energy.

Spectrophotometric optical system of microplate reader and filter wheel thereof

Shenzhen Mindray Bio-Medical Electronics Co., Ltd.