A measuring light source includes a hollow body having a diffusely reflective inner surface. Formed in the hollow body are a concave, concave mirror-shaped illumination space, a tubular light shaping space, and a concave, concave mirror-shaped light exit space, which have a shared axis. A light source for generating light is at least partially situated in the illumination space. The light exit space has a light exit. The illumination space and the light exit space with their concave mirror shapes are situated opposite one another and are connected by the tubular light shaping space. A diffusely reflecting reflective disk for reflecting the light, reflected from the inner surface of the hollow body situated in the light exit space, through the light exit to outside the hollow body is situated in the hollow body.

DE 10 2011 050 969 A1 discloses a device for the referenced measurement of reflected light, including a hollow body that has a diffusely scattering layer in its interior, and a light exit aperture. The device is switchable from a measurement position into a calibration position, as a result of which the light exit aperture is brought from a first detection axis into a second detection axis.
A measuring device is known from DE 10 2010 041 749 A1, having a cavity, extending in a longitudinal direction, with an opening that is to face toward a sample, and a plurality of openings situated in the longitudinal direction. A further opening is used for coupling in light.
U.S. Pat. No. 6,422,718 B1, DE 34 31 367 A1, and DE 20 2008 012 222 U1 disclose measuring light sources in various embodiments.
DE 10 2013 219 830 A1 teaches an optical device for reflection measurement under diffuse illumination, which includes a hollow body having a light-scattering surface in its interior, and a light exit aperture. The light exit aperture has a rotationally asymmetrical shape.
For detecting an absolute reflection spectrum, so-called VW systems and VN systems are known from the prior art which ensure that a reference measurement and a measurement of a sample differ only by the reflection on the sample.
DE 10 2014 215 193 A1 discloses a measuring system for detecting an absolute reflection spectrum of a sample. This measuring system includes a light source and a homogenizer for generating a uniform spatial illuminance distribution of the measuring light. The measuring system also includes a movable reflector and a receiver. The reflector is situated on the side of the sample as the light source. The homogenizer is preferably formed by an Ulbricht sphere or an Ulbricht tube, or by a sphere-cylinder design. In this measuring system, if the distance from the sample changes or the sample tilts, the Ulbricht sphere results in measuring errors of greater than 1% in the absolute measurement, which for many applications is too high. However, outside of laboratory conditions, in particular for inline measurements in production processes, changes in sample distance and sample tilting are unavoidable.
Proceeding from the prior art, the object of the present invention is to increase the uniformity of the spatial illuminance distribution of a measuring light in comparison to the measuring light that is generatable with an Ulbricht sphere, in order to able to carry out accurate measurements of an absolute reflection spectrum with less effort.
The stated object is achieved by a measuring light source according to appended Claim 1. The stated object is further achieved by a measuring systems according to the other appended independent Claims 6 and 11.
The measuring light source according to the invention is used for generating measuring light having a uniform spatial illuminance distribution. It is possible, for example, to conduct spectrometric analyses of surfaces by use of the measuring light source according to the invention. The measuring light source includes, first of all, a hollow body having a diffusely reflective inner surface. The interior is divided into a concave illumination space having the shape of a concave mirror, a tubular light shaping space, and a concave light exit space having the shape of a concave mirror, which have a shared axis. Thus, the concave mirror shape of the illumination space, the tubular shape of the light shaping space, and the concave mirror shape of the light exit space each have an axis, these axes coinciding and forming the axis of the hollow body and of the measuring light source. Although the illumination space and the light exit space each have a concave mirror shape, as mentioned they are diffusely reflective, and in this regard do not represent a concave mirror. The illumination space and the light exit space may also each be characterized as a concavely shaped reflector or as a concavely shaped Lambertian reflector.
A light source is at least partially situated in the illumination space. In any case, the light source is situated in such a way that it radiates light into the illumination space; the light source may be situated partially outside the illumination space. The light source is preferably situated on or in the axis. The light source is preferably situated in a focal point of the concave mirror shape of the illumination space.
The light exit space has a light exit through which light may pass from the light exit space to outside the hollow body. The light exit is preferably situated on or in the axis. The light passing from the light exit forms the measuring light that is generatable by the measuring light source.
The illumination space and the light exit space are situated with their concave mirror shapes, i.e., their concave reflector shapes, opposite one another. The inner sides of the concave mirror shapes or of the concave reflector shapes are oriented toward one another. The illumination space and the light exit space are preferably situated with their concave mirror shapes mirror-symmetrically opposite one another. However, the illumination space and the light exit space do not contact one another. The tubular light shaping space is situated between the illumination space and the light exit space, and connects the light shaping space and the illumination space. Light can thus pass into the light exit space via the light shaping space due to reflections on the inner surface of the hollow body from the illumination space. The concave mirror shape of the illumination space is preferably the same as the concave mirror shape of the light exit space. The concave mirror shape of the illumination space preferably merges continuously into the tubular shape of the light shaping space. The tubular shape of the light shaping space preferably merges continuously into the concave mirror shape of the light exit space. Thus, the extent of the concave mirror shape of the illumination space, the extent of the tubular shape of the light shaping space, and the extent of the concave mirror shape of the light exit space are preferably equal.
According to the invention, a diffusely reflecting reflective disk is situated in the hollow body. The reflective disk is used for reflecting the light that is reflected from the inner surface of the hollow body situated in the light exit space, so that the light is cast through the light exit to the outside of the hollow body. The reflective disk is preferably flat. The reflective disk is preferably nontransparent, i.e., opaque. The reflective disk shades the light exit from the light source, so that the light from the light source cannot directly pass through the light exit.
One particular advantage of the measuring light source according to the invention is that, due to the easily implemented modification of an Ulbricht sphere or an Ulbricht sphere-like sphere-cylinder arrangement, it allows generation of a measuring light having an extremely uniform spatial illuminance distribution.
The measuring light that is generatable with the measuring light source according to the invention has a deviation of its spatial illuminance distribution which preferably is no greater than 0.2%. This makes inline use of the measuring light source possible during a measurement of an absolute reflection spectrum, since the variance in the sample distance, the variation in the sample thickness, and tilting of the sample are tolerable.
The light that is generatable by the light source is preferably reflected in the hollow body three times before it exits the light exit. One of the at least three reflections takes place on the reflective disk. The light that is generatable by the light source is particularly preferably reflected in the hollow body at least four times before it exits the light exit. A majority of the light is reflected in the hollow body many times before it exits the light exit.
The diffusely reflective inner surface of the hollow body and the diffusely reflective surface of the reflective disk have a reflectance of preferably at least 96%, particularly preferably at least 98%, in the overall light spectrum. The diffusely reflective inner surface of the hollow body and the diffusely reflective surface of the reflective disk are preferably formed by a coating made of polytetrafluoroethylene (PTFE).
The light source preferably includes one or more light source elements, each of which is preferably formed by a halogen lamp, a flash lamp, a xenon flash lamp, a deuterium lamp, an IR emitter, an LED that emits in particular white light, a UV cathode, or a UV LED. The light source particularly preferably includes several of the light source elements, which preferably are formed by a halogen lamp, a white LED, and two UV LEDs. The individual light source elements preferably have the capability for independent switching and/or power modification.
The light source preferably includes one or more optical fibers via which the light source elements may radiate into the illumination space. The particular light source elements are not situated in the illumination space, but, rather, may be situated outside the illumination space. In any case, the optical fiber(s) of the light source open(s) into the illumination space, so that the light source is partially situated in the illumination space.
In preferred embodiments of the measuring light source according to the invention, the reflective disk is situated on the axis and perpendicular to the axis. The axis is preferably situated in the middle of the reflective disk. The reflective disk preferably has an oval, ellipsoidal, or circular shape.
The reflective disk is preferably designed to prevent the light source from directly illuminating the inner surface of the hollow body situated in the light exit space. The reflective disk is thus designed for shading the inner surface of the hollow body situated in the light exit space from the light source. This property of the opaque reflective disk is due essentially to the fact that it is designed for reflecting the light, which is reflected by the inner surface of the hollow body situated in the light exit space, through the light exit, for which purpose it is preferably situated on the axis and thus already shades the inner surface of the hollow body situated in the light exit space from the light source. In other respects, the position and the size of the reflective disk as well as the cross section and the length of the light shaping space must be coordinated with one another in such a way that the inner surface of the hollow body situated in the light exit space is shaded from the light source.
On its outer circumference the reflective disk preferably has a collar facing the light exit space. The collar shades the reflective disk from incident light striking laterally at a very small angle, and preferably has the same diffusely reflective surface as the overall cavity.
The reflective disk is preferably situated in the light exit space, in the light shaping space, or at a transition from the light exit space to the light shaping space. The latter-mentioned position is best suited for reflecting the light that is reflected from the inner surface of the hollow body situated in the light exit space and for guiding it through the light exit.
A light-shaping cylinder, on whose end facing the light exit space the reflective disk is situated, is preferably situated inside the light shaping space. The light-shaping cylinder preferably has the same diffusely reflective surface as the overall cavity. The light-shaping cylinder is preferably centrally situated in the tubular shape of the light shaping space. The light-shaping cylinder is preferably situated in the axis of the hollow body. The axis of the hollow body preferably also forms an axis of the light-shaping cylinder. The light-shaping cylinder preferably has the same axial length as the light shaping space. The light-shaping cylinder preferably has an oval, ellipsoidal, or circular cross section. The light-shaping cylinder is not irradiatable by the light source.
A hollow cylindrical reflection area that is designed for shaping and guiding the light exiting the illumination space toward the light exit space is provided between the lateral surface of the light-shaping cylinder and the inner lateral surface of the light shaping space. In addition, the light-shaping cylinder is designed to prevent the light source from directly illuminating the inner surface of the hollow body situated in the light exit space. As a result, the light-shaping cylinder is designed to shade the inner surface of the hollow body situated in the light exit space from the light source.
The light-shaping cylinder is preferably hollow at its axial end facing the illumination space, for example in order to provide further installation space for the light source.
The reflective disk and/or the light-shaping cylinder are/is preferably fastened via webs to the inner surface of the hollow body in the light shaping space. The webs preferably extend radially with respect to the axis. The webs preferably have the same diffusely reflective surface as the overall cavity.
The concave mirror shape of the illumination space is preferably formed by a hollow hemisphere. Alternatively, the concave mirror shape of the illumination space preferably has an ellipsoidal or oval cross section perpendicular to the axis.
The concave mirror shape of the light exit space is preferably formed by a hollow hemisphere. Alternatively, the concave mirror shape of the light exit space preferably has an ellipsoidal or oval cross section perpendicular to the axis.
The light exit is preferably closed by a protective glass, so that the cavity is closed by this protective glass.
The measuring system according to the invention is used for detecting an absolute reflection spectrum of a sample. The measuring system is used, for example, for an inline measurement in a production process for large coated surfaces, such as glass disks or films, in order to inspect the surface. A reference sample is not necessary for detecting the absolute reflection spectrum. The measuring system therefore also allows a reference measurement of a measuring light that is used.
A first embodiment of the measuring system includes, firstly, the measuring light source according to the invention for generating the measuring light having a uniform spatial illuminance distribution.
The first embodiment of the measuring system also includes an optical receiver, situated opposite from the measuring light source, for receiving light. The light to be received is the measuring light of the measuring light source after it has traveled a path over the sample, or a reference path. An entry opening of the receiver and an exit opening of the measuring light source are aligned with one another, except for an offset.
The first embodiment of the measuring system is designed to be situated parallel to a surface of the sample. In particular, the axis of the measuring light source is to be situated parallel to the surface of the sample, namely, with an offset with respect to the surface of the sample.
The first embodiment of the measuring system includes a first mirror that is situated on the axis of the measuring light source and aligned for reflecting the measuring light of the measuring light source, exiting the light exit, onto the sample. The first mirror is preferably rigidly mounted.
The first embodiment of the measuring system also includes a second mirror that is adjustable in at least two positions. In a first position, the second mirror is aligned for reflecting the measuring light, reflected from the first mirror, to the receiver. The first position is thus designed for a reference measurement, since on its path from the measuring light source to the receiver, the measuring light passes the components of the measuring system, in particular the first and second mirrors, but not the sample. In this regard, the first mirror is also aligned for reflecting the measuring light of the measuring light source, exiting the light exit, onto the second mirror. In a second position, the second mirror is aligned for reflecting the measuring light, reflected from the sample, to the receiver. The second position is thus designed for a reflection measurement, since on its path from the measuring light source to the receiver, the measuring light is reflected from the sample.
The measuring light source, the receiver, the first mirror, and the second mirror are preferably situated together on one side of the sample. Correspondingly, the measuring light source, the receiver, the first mirror, and the second mirror are designed so that they are situated together on one side of the sample.
One particular advantage of the first embodiment of the measuring system according to the invention is that it may have a very compact design. The measuring light source and the receiver may be situated in one plane with only a slight offset, while the first mirror and the second mirror may be positioned in a space-saving manner between the measuring light source and the receiver.
The optical receiver is preferably formed by an optical sensor, such as a spectrometer in particular, or is formed at least by an optical input of the optical sensor. For example, the optical receiver may be formed by an input optical system to which an optical fiber that leads to a spectrometer is connected.
The receiver has an axis in which it receives incident light. In the first embodiment of the measuring system according to the invention, the axis of the receiver and the axis of the measuring light source are particularly preferably situated in parallel, and have an offset, i.e., are spaced apart from one another. However, this offset may be small. The offset is preferably smaller than a maximum extension of the hollow body in a direction perpendicular to the axis of the measuring light source. The second mirror is preferably situated on the axis of the receiver.
In the first embodiment of the measuring system according to the invention, the first mirror is preferably inclined toward the sample at an angle of 45° with respect to the axis of the measuring light source. The measuring light from the measuring light source is thus deflected by 90° with respect to the axis of the measuring light source, and when the second mirror is in the second position, may strike the surface of the sample perpendicularly.
In the first embodiment of the measuring system according to the invention, the second mirror is preferably to be adjusted by pivoting the second mirror from its first position into its second position, and vice versa. The second mirror is thus preferably stationary but rotatable. The axis of this pivoting movement is preferably formed by one of the four sides of the preferably rectangular second mirror. The axis of this pivoting movement is preferably perpendicular to the axis of the receiver and parallel to the surface of the sample.
In the first embodiment of the measuring system according to the invention, the second mirror in its first position is preferably inclined toward the first mirror at an angle of 45°±5° with respect to the axis of the receiver. The measuring light reflected from the first mirror, which is preferably oriented at an angle of 90° with respect to the axis of the measuring light source or of the receiver, is thus deflected again by 90°, so that it may pass to the receiver in the axis of the optical receiver.
In the first embodiment of the measuring system according to the invention, the second mirror in its second position is preferably inclined toward the sample at an angle of 45°±5° with respect to the axis of the receiver. The measuring light reflected from the sample is thus deflected, so that it may pass to the receiver in the axis of the receiver.
In the first embodiment of the measuring system according to the invention, the second mirror is preferably pivotable between its first position, its second position, and a third position. The third position is designed for a transmission measurement of the sample. For this purpose, the measuring system also includes a fourth mirror that is situated on the side of the sample opposite from the first mirror. The fourth mirror is designed for reflecting the measuring light, reflected from the first mirror and transmitted by the sample, back to the sample and to the second mirror. The sample thus transmits the measuring light exactly twice, namely, a first time, before it strikes the fourth mirror, and a second time, after it has been reflected from the fourth mirror. The twice-transmitted measuring light is then reflected from the second mirror to the receiver. The fourth mirror is preferably rigidly mounted. The fourth mirror is preferably situated parallel to the axis of the measuring light source and preferably parallel to the flat sample.
In the first embodiment of the measuring system according to the invention, the second mirror in its third position is further inclined with respect to the sample than in its second position. The second mirror in its third position is preferably inclined toward the sample at an angle between 40° and 70°, in particular between 47° and 60°, with respect to the axis of the receiver.
The second mirror is preferably pivotable between its first position, its second position, and a fourth position, the fourth position being designed for a dark measurement. The second mirror does not cast measuring light onto the receiver in this fourth position. For this purpose, the second mirror in its fourth position is preferably oriented toward the receiver perpendicularly with respect to the axis of the receiver. The dark measurement together with the reference measurement is used for balancing the measuring system in order to be able to make an accurate measurement of the absolute reflection spectrum, using the measuring system.
In the first embodiment of the measuring system according to the invention, the second mirror is preferably pivotable between its first position, its second position, its third position, and its fourth position.
The measuring light source, the receiver, the first mirror, and the second mirror preferably form a measuring head. The measuring head includes a housing in which the measuring light source, the receiver, the first mirror, and the second mirror are situated. The housing has a measuring opening through which the measuring light reflected from the first mirror may pass outwardly, and through which the measuring light reflected from the sample may pass inwardly to the second mirror.
A second embodiment of the measuring system includes, firstly, a measuring light source for generating the measuring light having a uniform spatial illuminance distribution. The measuring light source has a light exit that is situated on or in an axis of the measuring light source. The light exiting the light exit forms the measuring light that is generatable by the measuring light source. This measuring light source is preferably formed by the above-described measuring light source according to the invention.
The second embodiment of the measuring system also includes an optical receiver, situated opposite from the measuring light source, for receiving light. The light to be received is the measuring light of the measuring light source after it has traveled a path over the sample, or a reference path. An entry opening of the receiver and an exit opening of the measuring light source are aligned with one another, except for a possible offset. The receiver has an axis in which it receives incident light.
The second embodiment of the measuring system is designed to be situated parallel to a surface of the sample. In particular, the axis of the measuring light source is to be situated parallel to the surface of the sample, namely, with an offset with respect to the surface of the sample.
The second embodiment of the measuring system includes a first mirror that is situated on or in the axis of the optical receiver and aligned for reflecting the light reflected from the sample to the optical receiver. The first mirror is preferably rigidly mounted.
The second embodiment of the measuring system also includes a second mirror that is adjustable in at least two positions. In a first position, the second mirror is aligned for reflecting the measuring light, exiting the light exit, onto the first mirror. The first position is thus designed for a reference measurement, since on its path from the measuring light source to the receiver, the measuring light passes the components of the measuring system, in particular the first and second mirrors, but not the sample. In this regard, the first mirror is also aligned for reflecting the light reflected from the second mirror to the optical receiver. In a second position, the second mirror is aligned for reflecting the measuring light, exiting the light exit, onto the sample. The second position is thus designed for a reflection measurement, since on its path from the measuring light source to the receiver, the measuring light is reflected from the sample.
The measuring light source, the receiver, the first mirror, and the second mirror are preferably situated together on one side of the sample. Correspondingly, the measuring light source, the receiver, the first mirror, and the second mirror are designed to be situated together on one side of the sample.
One particular advantage of the second embodiment of the measuring system according to the invention is that it may have a very compact design. The measuring light source and the receiver may be situated in one plane with only a slight offset, while the first mirror and the second mirror may be positioned in a space-saving manner between the measuring light source and the receiver.
The second embodiment of the measuring system is suitable for measuring samples having greatly different thicknesses. The measuring system according to the invention is preferably designed for measuring a sample having a thickness of up to 20 mm. The measuring system according to the invention is preferably designed for measuring glass disks. Of course, samples having a negligibly small thickness in the nm or μm range may also be measured using the measuring system according to the invention.
The optical receiver is preferably formed by an optical sensor, such as a spectrometer in particular, or is formed at least by an optical input of the optical sensor. For example, the optical receiver may be formed by an input optical system to which an optical fiber that leads to a spectrometer is connected.
In the second embodiment of the measuring system according to the invention, the axis of the receiver and the axis of the measuring light source are particularly preferably situated in parallel, and have an offset, i.e., are spaced apart from one another. However, this offset may be small. The offset is preferably smaller than one-half the maximum extension of the measuring light source in a direction perpendicular to the axis of the measuring light source.
The second mirror in its first position and in its second position is situated in each case on or in the axis of the measuring light source, so that the measuring light exiting the light exit strikes the second mirror.
In the second embodiment of the measuring system according to the invention, the first mirror is preferably inclined toward the sample at an angle of 45°±5° with respect to the axis of the optical receiver. When the second mirror is not in its first position, the measuring light that is reflected from the sample and that strikes the first mirror is thus deflected by approximately 90° and strikes the optical receiver.
In the second embodiment of the measuring system according to the invention, the second mirror is preferably to be adjusted by pivoting the second mirror from its first position into its second position, and vice versa. The second mirror is thus preferably stationary but rotatable or pivotable. The axis of this pivoting movement is preferably formed by one of the four sides of the preferably rectangular second mirror. The axis of this pivoting movement is preferably perpendicular to the axis of the measuring light source and parallel to the surface of the sample. The axis of this pivoting movement is preferably situated between the axis of the measuring light source and the axis of the optical receiver.
In the second embodiment of the measuring system according to the invention, the second mirror in its first position is preferably inclined and oriented toward the first mirror at an angle of 50°±5° with respect to the axis of the measuring light source. The measuring light exiting the light exit, which is preferably situated in the axis of the measuring light source, is thus deflected by approximately 90° by the second mirror, so that it strikes the first mirror approximately perpendicularly with respect to the axis of the optical receiver, from which it is once again deflected by 90°, so that it strikes the optical receiver.
The second mirror in its second position is preferably inclined and oriented toward the sample at an angle of 50°±5° with respect to the axis of the measuring light source. The measuring light exiting the light exit is thus deflected so that it strikes the sample.
In the second embodiment of the measuring system according to the invention, the second mirror is preferably adjustable between its first position, its second position, and a third position. The third position is designed for a transmission measurement of the sample. For this purpose, the measuring system also includes a third mirror that is situated on the axis of the measuring light source and oriented toward the sample for reflecting the measuring light exiting the light exit. The third mirror is preferably rigidly mounted. The third mirror is preferably inclined toward the sample at an angle of 45°±5° with respect to the axis of the measuring light source. The second embodiment of the measuring system also includes a fourth mirror that is situated on the side of the sample opposite from the third mirror. The fourth mirror is aligned for reflecting the measuring light, reflected from the third mirror and transmitted by the sample, back to the sample and to the first mirror. The sample thus transmits the measuring light exactly twice, namely, a first time, before it strikes the fourth mirror, and a second time, after it has been reflected from the fourth mirror. The twice-transmitted measuring light is then reflected from the first mirror to the optical receiver. The fourth mirror is preferably rigidly mounted. The fourth mirror is preferably situated parallel to the axis of the measuring light source and preferably parallel to the flat sample.
In the second embodiment of the measuring system according to the invention, the second mirror is preferably adjustable by pivoting between its first position, its second position, and its third position.
In the second embodiment of the measuring system according to the invention, the second mirror in its third position is aligned in such a way that it enables a beam path from the light exit to the third mirror. Thus, the second mirror in its third position is preferably not situated in the beam path. The second mirror in its third position is preferably inclined at an angle between −20° and 20° with respect to the axis of the measuring light source, and is spaced apart from this axis.
In the described preferred embodiments, the second mirror must be pivoted by an angle of preferably 60°±20°, more preferably 60°±5°, for changing from its second position, which is suitable for a reflection measurement, to its third position, which is suitable for a transmission measurement, and vice versa. This comparatively large pivot angle results in a high photometric accuracy in particular for the transmission measurement, since skewing of the measurement by reflection signals is largely avoided in the transmission measurement.
In the second embodiment of the measuring system according to the invention, the second mirror is preferably adjustable between its first position, its second position, and a fourth position, the fourth position being designed for a dark measurement. The second mirror does not cast measuring light onto the sample in this fourth position. The second mirror in its fourth position is aligned in such a way that it enables a beam path from the sample to the first mirror. Thus, the second mirror in its fourth position is preferably not situated in the beam path from the sample to the first mirror. In the fourth position, the second mirror is preferably aligned in such a way that it reflects the measuring light, exiting the light exit, back to the light exit. For this purpose, the second mirror in its fourth position is preferably aligned perpendicularly with respect to the axis of the measuring light source. Measuring light is not directed onto the sample from any of the mirrors. The dark measurement together with the reference measurement is used for balancing the measuring system in order to be able to make an accurate measurement of the absolute reflection spectrum, using the measuring system.
In the second embodiment of the measuring system according to the invention, the second mirror is preferably adjustable by pivoting between its first position, its second position, and its fourth position.
The second mirror is preferably adjustable between its first position, its second position, its third position, and its fourth position. The second mirror is preferably pivotable between its first position, its second position, its third position, and its fourth position.
The measuring light source, the receiver, the first mirror, the second mirror, and optionally the third mirror preferably form a measuring head. The measuring head includes a housing in which the measuring light source, the receiver, the first mirror, the second mirror, and optionally the third mirror are situated. The housing has a measuring opening through which the measuring light reflected from the second mirror and optionally the measuring light reflected from the third mirror second may pass outwardly, and through which the measuring light reflected from the sample and optionally the measuring light reflected from the fourth mirror may pass inwardly to the first mirror.
The measuring light source in the described embodiments of the measuring system according to the invention is preferably formed by one of the described preferred embodiments of the measuring light source according to the invention. In other respects, the described embodiments of the measuring system according to the invention preferably also have other features, which are stated in conjunction with the measuring light source according to the invention and its preferred embodiments.

Measuring light source, and measuring system for detecting a reflection spectrum


A microprocessor comprises an internal address bus having a first portion (2,4) having a plurality of conductors carrying the low order address byte and a second portion (10) having a plurality of conductors for carrying the high order address byte. The microprocessor further comprises a plurality of registers, including an incrementor (12,13), a program counter (14,15), a temporary register (16,17), a stack pointer (18,19), an index register (20,21), and an accumulator (22,24), each comprising a pair of 8-bit registers for temporarily storing information. An arithmetic logic unit (28) performs computational operations on digital information within the microprocessor. The microprocessor includes a pair of internal data buses (6,8) each having a plurality of conductors for conducting digital information within the microprocessor. Means are provided for coupling selected ones of the registers, or the high or low order portions thereof, to the first and second data buses. The provision plural internal data buses permits a greater number of transfers of digital information to occur within the microprocessor during each machine cycle. The result is more efficient microprocessor operation and higher throughput.

Microcomputers are sophisticated, general purpose logic devices which can be programmed to perform a wide variety of useful control functions in industrial and communications equipment, large-scale and medium-scale computer peripheral and terminal hardware, automobiles and other transportation media, amusement and educational devices, and the like. Generally, an entire spectrum of microcomputers is presently available in the commercial marketplace. As the speed of operation, or throughput, of a microcomputer increases, the more valuable and more versatile the microcomputer becomes, since it is able to control a given operation more efficiently and more accurately, or to control a greater number of operations simultaneously, or to control operations requiring relatively fast response times.
The throughput of any given microcomputer is a function of, among other things, the number of machine cycles required to execute a given set of instructions. In the course of designing any computer system, and in particular a microcomputer, a set of instructions is selected which will provide the anticipated programming requirements for the projected market in which the computer system is to be used. The microprocessor, or processor component of a single-chip microcomputer, executes each instruction as a sequence of machine cycles, with the more complex instructions consuming a greater number of machine cycles. The operation of the internal registers and gating circuitry of the microprocessor is synchronized by means of a master clock signal applied to the microprocessor. The master clock signal may actually comprise two or even four clock components; i.e., the microprocessor clock may be two-phase or four-phase. During the basic clock cycle known as the machine cycle, a number of internal processor-related operations may take place simultaneously, including the transfer of digital information from a bus to a register or vice versa, between certain registers, from an address or data buffer to a bus or vice versa, and so forth, or the individual conductors of a bus may each be set to a predetermined logic level, or the contents of a register may be set to a predetermined logic level. The more processor operations occurring within an individual machine cycle the fewer the number of machine cycles required for the execution of a particular instruction. Thus it is desirable to maximize to the extent possible the number of internal processor operations occurring within a given machine cycle.
The MC6800 microprocessor commercially available from Motorola, Inc. is a prior art microprocessor device which has found wide commercial acceptance. The aforementioned microprocessor includes a number of features intended to minimize the number of machine cycles per instruction, including those features described in U.S. Pat. Nos. 4,030,079, 4,016,546, 4,040,035, 4,032,896, and 3,962,682. While the throughput of the MC6800 has been found satisfactory for many applications, any significant improvement in the throughput of such microprocessor would enhance its commercial acceptance for the reasons given above.
In addition to the need to increase microprocessor throughput by minimizing the number of machine cycles per instruction execution, it is desirable to provide a microprocessor with structure which facilitates the addition of new instructions to the microprocessor instruction set.

Microprocessor having plural internal data buses


A process for electrowinning metal in a low temperature melt is disclosed. The process utilizes an inert anode for the production of metal such as aluminum using low surface area anodes at high current densities.

The Hall-Heroult process was first used commercially around 1900. In this process, aluminum is extracted by electrolyzing aluminum oxide (also known as "alumina") dissolved in a molten salt bath based on cryolite, Na.sub.3 AlF.sub.6. The molten cryolite is operated at a temperature generally with the range of 950.degree.-1000.degree. C. In the electrolytic cell, a carbon lining within a crucible typically serves as the cathode, and the anodes, typically carbon, are immersed in the molten salt. The molten cryolite-aluminum oxide serves as the electrolyte solution. Heat produced, for example, by a large electric current in the cell, melts the cryolite which dissolves the aluminum oxide and maintains the aluminum being electrolyzed in the molten state in which it collects in the bottom of the cell.
The Hall process, although commercial today, has certain limitations, such as the requirement that the process operate at relatively high temperatures, typically around 970.degree. C.
The high cell temperatures are necessary to achieve a high alumina solubility. At these temperatures, the electrolyte and molten aluminum progressively react with most carbon or ceramic materials, creating problems of metal and electrolyte containment and cell design.
The high temperature salt baths of the prior art are typically enveloped in a frozen sidewall and/or frozen ledge of salt bath, which helps reduce the corrosive effects of the electrolyte and metal on the containment vessel. Maintaining a frozen sidewall or ledge, however, requires a significant heat loss from the system, and any attempt to insulate the system to significantly conserve heat loss results in the melting of the frozen ledge or sidewall.
In general, the carbon anodes are consumed in the Hall process with the evolution of carbon oxide. Practically speaking, the consumption of carbon anodes requires adjustment of the anode-cathode distance to maintain it within certain critical limits. Although 0.33 kg of carbon is theoretically required for each kilogram of aluminum produced, nearly 0.5 kilograms of carbon per kilogram of aluminum can actually be consumed, for instance by losses due to air burning and back reaction between aluminum and CO.sub.2. Purity requirements for the aluminum produced necessitate the use of high quality coke for the anodes. In the United States alone, carbon consumption for the production of aluminum is nearly 2-5 million tons per year. If an inert anode could be found to replace the carbon anodes the energy content of the coke could be saved, and O.sub.2, rather than carbon oxide would be produced at the anode. In addition, emissions of fluorocarbons and sulfur would be eliminated.
Other disadvantages of the Hall cell include sodium intercalation and formation of sodium aluminum oxide which causes heaving and cracking of the cell lining, with resulting interference in operating characteristics of the cell and shortened cell life, requiring periodic cell relining.
Numerous methods have been attempted to overcome some or all of the above shortcomings of the Hall process. While many of these methods have met with some success, none has replaced the conventional Hall process in commercial applications. One attempt has been to utilize so-called "low temperature" salt baths which allow reduced energy consumption at the expense of lower alumina solubility. For example, U.S. Pat. No. 3,951,763 discloses a low temperature salt bath and uses a carbon anode, which is consumed in the process. U.S. Pat. No. 3,996,117 adds 5% to 10% by weight LiF to the bath.
One of the drawbacks of the low temperature salt bath technology has been the realization that reduction of salt bath temperature likewise leads to reduction of alumina solubility. Attempts to overcome this problem include those disclosed in U.S. Pat. No. 3,852,173 wherein the alumina is provided with a sufficient water content to prevent anode dusting, which water content also assists in dispersing the alumina into the low temperature salt bath solution of NaF/AlF.sub.3. However, providing the water-containing alumina is an added requirement of the process and naturally incurs added expense.
Attempts at operating the salt bath at lower temperatures by using progressively lower bath weight ratios than the 1.1:1 NaF to AlF.sub.3 bath ratios typically used have been frustrated by the formation of a crust of frozen electrolyte over the molten aluminum as electrolysis proceeds. This crust drastically increases resistance at the cathode, reduces metal coalescence and causes deposition of sodium, which in turn, hampers current efficiency. Under these conditions, the cell can no longer be operated efficiently.
Various attempts have been made to utilize so-called "inert" anodes in order to improve the Hall process. See, e.g., U.S. Pat. Nos. 3,718,550; 3,960,678; 4,098,669; 4,233,148; 4,454,015; 4,478,693; 4,620,905, 4,620,915 and 4,500,406. Attempts have also been made to use inert anodes with low temperature salt baths. U.S. Pat. No. 4,455,211 discloses a low temperature salt bath of NaF/AlF.sub.3 which teaches the addition of 1% to 15% LiF and an inert anode made of an interwoven matrix. PCT Application No. WO 89/06289 discloses the use of an inert anode in connection with a metal chloride and/or metal fluoride salt bath using additives for low temperature aluminum electrolysis. However, this reference teaches the need to increase the actual anode surface area by 2 to 15 times the superficial or projected anode surface area. Such increased surface area anodes are typically fabricated, for example, by drilling numerous holes deep into the anode or using an array of plates or rods for anodes. Such anodes typically have an active surface area several times the cathode active surface area.
U.S. Pat. No. 4,681,671 discloses a low temperature salt bath which is used in conjunction with an anode having a relatively large surface area (actual or active area at least 1.5 times larger than the projected surface area) and low current density. Indeed, this reference teaches the necessity of utilizing a low current density and increased anode surface area in conjunction with low temperature salt baths and inert anodes.

Process and apparatus for low temperature electrolysis of oxides


A shift control apparatus for a vehicle automatic transmission, including: a device for determining whether an intake air quantity (Q/N) per revolution of a vehicle engine exceeds a predetermined threshold; a memory for storing a first and a second shift control data map for shifting a vehicle transmission, the first shift control data map representing first shift boundary lines each representing a relationship between the vehicle speed (SPD) and the intake air quantity, while the second shift control data representing second shift boundary lines each representing a relationship between the vehicle speed and a shift control parameter (TA, PA) which reflects an operation amount of an accelerator pedal; a map switching device for selecting one of the first and second shift control data maps, the map switching device replacing the first shift control data map by the second shift control data map when the intake air quantity exceeds the predetermined threshold; and a device for shifting the transmission, according to the selected first or second shift boundary lines.

1. Field of the Invention
The present invention relates generally to an apparatus for controlling an automatic transmission of a motor vehicle, and more particularly to such an automatic transmission shift control apparatus for selecting an optimum operating position of the automatic transmission, according to shift boundary lines using an intake air quantity per revolution of the vehicle engine.
2. Discussion of the Prior Art
There is known a shift control apparatus for automatically controlling a vehicle automatic transmission, according to shift boundary lines which are represented by stored data maps and each of which represents a relationship between a throttle valve opening TA and the vehicle speed. The determination of whether the transmission is shifted down or up is effected by determining whether a point defined by the currently detected throttle valve opening and vehicle speed is positioned on one or the other side of the shift-down or shift-up boundary line which corresponds to the currently selected position of the transmission. Some modern vehicle engines are equipped with various devices such as a valve timing changing device, a swirl control valve device and an idling speed adjusting device. The operations of these devices may change the engine torque or torque characteristics. If the known shift control apparatus as indicated above is used for such engine, the transmission may be undesirably shifted at a varying drive torque, since the engine torque tends to fluctuate even with the same throttle valve opening. As a result, the transmission may be shifted frequently in a short period of time, or suffer from a considerable torque variation or shock upon shifting actions.
In view of the above drawback, there has been used an electronic shift control apparatus as disclosed in laid-open Publication No. 60-34563 of unexamined Japanese Patent Application. This shift control apparatus uses shift boundary lines each representing a relationship between the vehicle speed, and an intake air quantity Q/N per revolution of the vehicle engine, namely, an intake air quantity Q divided by an engine speed N. These parameters Q and N are detected by respective sensors. Since the intake air quantity Q/N per revolution of the engine (hereinafter referred to simply as "intake air quantity Q/N") accurately represents the engine torque, the transmission can be smoothly shifted, without busy or frequent shifting actions or a shifting shock.
However, the shift control apparatus using the intake air quantity Q/N and the vehicle speed for the shift boundary lines suffer from poor vehicle acceleration smoothness and response to the operation of the accelerator pedal, as felt by the vehicle driver. That is, the intake air quantity Q/N reaches the maximum value, and the engine torque reaches 90% or higher of the maximum value, when the throttle valve opening TA (hereinafter referred to as "throttle opening TA") is increased to a level of about 50-60%. Therefore, the driver's depression of the accelerator pedal to increase the throttle opening TA from that 50-60% level will not result in a considerable increase in the engine torque, whereby the vehicle acceleration as felt by the vehicle driver is bottomed at about 50-60% of the throttle opening.
The vehicle using the shift control apparatus as described above suffers from another problem, where the vehicle engine is provided with a turbocharger, a valve timing changing device or a swirl control valve device. More particularly, the intake air quantity Q/N which reflects the engine torque may increase, without depression of an accelerator pedal or without an increase in the opening of the throttle valve, due to an effect of the turbocharger, for example. As a result, the transmission may be commanded to be shifted down. This shift-down action is unexpected by the vehicle driver, since the driver is not requiring acceleration of the vehicle, i.e., is not depressing the accelerator pedal to increase the throttle opening. Namely, the vehicle driver depresses the accelerator pedal to increase the throttle opening to a given level, and the throttle opening is held constant with the accelerator pedal kept at the same position by the driver. The intake air quantity and the engine torque suddenly rise a considerable time after the depression of the accelerator pedal, due to the effect of the turbocharger. Consequently, the transmission may be shifted down unexpectedly to the vehicle driver, since the vehicle is not in the process of deceleration and the accelerator pedal is held at the same position.

Vehicle transmission shift control apparatus using shift boundary lines based on vehicle speed, and engine intake air quantity or throttle or accelerator operation amount


Ozonated liquid is mixed within a multi-stage clarifier system with wastewater to be treated and suspended solids are removed. The clarified effluent is filtered and exposed to ultraviolet radiation. Ozone is injected into the irradiated effluent and received within a contact tower where reaction between the contaminants and ozone takes place. The ultraviolet irradiated, ozonated, and clarified liquid is recirculated through an ozone injector and discharged through a mixer plate into a purge chamber. The purge chamber effluent is split, with a portion returning to the contact tower and passing through a second ultraviolet radiation source, and the remaining purge chamber effluent being distributed within the clarifiers. After a predetermined residence within the system, a diverter valve in the return line is operable to discharge the treated water through a carbon filter and out of the system. The recirculation of the UV irradiated ozonated liquid provides both effective solids removal and reaction of the contaminants with the ozone to produce an acceptable treated water.

With increased attention and regulatory resources being directed to the establishment and maintenance of uncontaminated rivers, lakes, and groundwater, it has become imperative for the producer of wastewater to employ a treatment system which avoids the introduction of prohibited levels of contaminants into the surroundings.
In many states groundwater control regulations of exacting strictness have been enacted. Commonly, these regulations require the immediate report of and remediation of any discharges of organic and inorganic wastes, soluble heavy metals, petroleum products, or bacterialogically contaminated materials, which exceed regulatory levels. Although it is always an option to transport the contaminated wastewater to an off-site authorized disposal facility, such transportation is in most circumstances prohibitively expensive due to the large volume of wastewater involved. Furthermore, transportation of wastes deemed "hazardous" may require prior authorization and permitting from regulatory authorities. Rural, residential and agribusiness sources of wastewater are particularly in need of effective treatment systems. Wastewater generators which are not connected with City sewage must independently arrange for disposal of wastewater. For individual and small business wastewater producers, it is essential that the wastewater treatment system be compact and low cost to operate.
Wastewater may contain human wastes, cooking wastes including grease and animal matter, petroleum products, pesticides, lead based paints, and any number of other wastes which are typically associated with water through common cleaning and waste disposal processes. These wastes are typically high in their biochemical oxygen demand (BOD), and their suspended solids (SS) levels.
Known systems have introduced oxidants, in particular ozone, into wastewater. This ozone injection causes inorganic contaminants to oxidize to less soluble oxides and converts organic components to carbonaceous residues and carbon dioxide. Known apparatus has utilized ozone injectors and other equipment involving pressure and velocity changes of wastewater streams to introduce the ozone in the form of a vast quantity of microscopic bubbles. The ozone bubbles tend to form about suspended solid particles and float those particles to the surface of a body of liquid. Clarifiers have been conventionally used which collect the floated solids from the water surface and separate the solids from the wastewater. To achieve higher levels of contaminant removal, wastewater systems have been employed which recirculate all or a portion of the treated wastewater through repeated cycles of ozone injection and clarification.
It has long been known that bacterial impurities may be eliminated by exposure to ultraviolet radiation. Ultraviolet light sources adapted for in-line use within fluid treatment systems are readily available. These UV sources are positioned within the system to expose the effluent prior to its exit from the system. Common ozone generators utilize an electric arc. Thus ozone generation presents significant demands for electric power and hence increases the cost of wastewater treatment.
What is needed is a wastewater treatment system which may be economically employed by small to medium users, and which effectively eliminates objectionable quantities of contaminants from wastewater such that system effluents may be freely disposed of.

UV-enhanced ozone wastewater treatment system


Method and corresponding circuit for estimating motion between pictures composed of interlaced fields. Conventionally, such a circuit comprises a channel for searching for the optimum frame vector, which channel is autonomous with respect to that for searching for the optimum field vectors. In accordance with the invention, the channel for searching for the optimum field vectors is unchanged, but for searching for the optimum frame vector the channel comprises two branches which are no longer autonomous but are arranged at the respective output of each sub-stage for searching for the field vector of the channel with a view to determining an approximation of the motion vector which is sufficient for the searched estimation.

The invention relates to a method of estimating motion between pictures composed of two interlaced fields divided into blocks of pixels, which method comprises a step of searching the motion vector which is most representative of the motion between two pictures, referred to as optimum frame vector, and a step of searching the motion vector which is most representative of the motion between two fields, referred to as optimum field vector, which comprises, in parallel, two sub-steps each comprising, in series, a search for the field vector by way of block matching and a refinement of the search to within half a pixel.
The invention also relates to a circuit for estimating motion between pictures composed of two interlaced fields divided into blocks of pixels, which circuit comprises means for searching the motion vector which is most representative of the motion between two pictures, referred to as optimum frame vector, and means for searching the motion vector which is most representative of the motion between two fields, referred to as optimum field vector, said means for searching the optimum field vector comprising means for searching a field vector by way of block matching and means for refining such a search to within half a pixel.
The invention finally relates to a coding device comprising such a motion estimation circuit.
This invention is widely used in the field of digital data compression before transmission and/or storage of these data, and particularly for realising a device for coding digital television signals which are compatible with the MPEG2 standard.
It is known that the transmission in a digital form of a television picture at the actual definition requires bitrates (and would require even more bitrates at a higher definition) necessitating channels having a very wide band (for example, a sequence of colour pictures of 25 frames per second generates a digital data stream of just over 165 million bits per second). The direct transmission of such a quantity of information cannot be realised economically and, in order that this information can make use of the existing networks for data transmission and storage media, the number of data is compressed. This compression is obtained essentially by utilizing the strong spatial and temporal correlation between neighbouring pixels, as will hereinafter be described in greater detail.
First, it will be useful to recall the main characteristics of the MPEG2 standard. A sequence of digital signals in conformity with this standard comprises information relating to the luminance component Y and the chrominance components, or colour difference signals U and V (the grey levels for the luminance Y and the colour levels for the signals U and V are expressed in digital words of 8 bits). In accordance with the input format provided by the MPEG standard, the chrominance is subjected to a sub-sampling by four with respect to the luminance. There are thus two values which are related to the colour (one for U, the other for V) for four luminance values. As the matrices of words of 8 bits are arranged in blocks of 8.times.8 pixels, four adjacent blocks of the matrix Y correspond to one block of the matrix U and one block of the matrix V, and these six blocks combined constitute a macroblock (these blocks and macroblocks are the picture subdivision units which are subjected to coding, as in the example cited hereinbefore). Finally, a regrouped series of macroblocks constitutes a slice and each picture is composed of a given number of slices, for example 36 in the example described.
The pictures (the assembly of digital signals corresponding thereto is also concisely referred to as such) are of three types in a stream of MPEG data, dependent on the coding mode applied. The simplest are the pictures I (Intraframe coded pictures) in which all the macroblocks are coded independently of any other picture. If the transmission channel is modified or the bitrate is switched, one should expect such a picture of the type I for reconstituting the new information resulting from said modification at the decoding end. The pictures P (Predictive coded pictures) constitute a second type of pictures which are predicted by unidirectional motion compensation based on a preceding picture (of the type I or of the type P itself) and which thus only contain macroblocks of the type P or of the type I. Finally, the pictures B (Bidirectionally predictive coded pictures) predicted by bidirectional motion compensation based on a previous picture and a subsequent picture (which are themselves of the type I and/or P) may indifferently contain macroblocks of the type I, P or B.
A data stream comprises six information levels (each level including the lower level and some additional information components). The sequence of pictures corresponds to the highest level. This sequence is composed of a succession of groups of pictures (or GOP) each comprising a given number of pictures. A picture such as is shown in FIG. 1 includes a given number n of picture slices S.sub.1 to S.sub.n, each picture slice includes a given number of macroblocks MB and each macroblock MB comprises a given number r of blocks, here 6 (Y.sub.1, Y.sub.2, Y.sub.3, Y.sub.4, U, V) which constitute the last level.
After the description of the MPEG standard features and before the description of the invention, an example of a state-of-the-art coding device will be now described. Such a device, shown in FIG. 2, comprises a coding channel which includes, in series, a discrete cosine transform circuit (DCT), a quantizing circuit 2 and a variable-length coding circuit 3 (VLC). This DCT transform circuit 1 receives, via a subtracter 19 mentioned below, digital signals which correspond to the input video signals of the coding device (obtained, more specifically, by the difference between these input signals and the predicted signals which are present at the other input of the subtracter) and which are available in the form of blocks, here having the format of 8.times.8 pixels. This circuit 1 converts these signal blocks into blocks of 8.times.8 coefficients whose first coefficient represents the average value of the grey levels of the pixels of the block considered and whose sixty-three other coefficients represent the different spatial frequencies in this block.
The quantizing circuit 2 quantizes each of these output coefficients of the circuit 1. On the one hand, this quantization is related to the position of the coefficient considered in the 8.times.8 block (the high spatial frequencies are less perceptible to the human eye and corresponding coefficients may thus be quantized with a quantization step which is larger and gives a less precise quantization) and on the other hand to a quantization factor which is related to the bitrate. The values resulting from this quantization are then applied to the variable-length coding circuit 3, the output of which is connected in a bitrate control stage 15 to a buffer memory 4 for storing the coded words, whose output constitutes that of the coding device. As a function of the fullness of this memory 4, a bitrate control circuit 5 arranged at the output of said memory applies the quantization factor mentioned above to the quantizing circuit 2, and the value of this factor, related to this fullness, provides the possibility of modifying the quantization step in such a way that said memory 4 neither overflows nor underflows. Such a coding chain with bitrate control is known and will not be further described.
The values resulting from the quantization are also applied to a prediction channel including, in series, an inverse quantizing circuit 6 (denoted Q.sup.-1), an inverse discrete cosine transform circuit 7 (denoted DCT.sup.-1), an adder 8, a picture memory 9, a circuit 18 for motion estimation and compensation based on the original picture and the non-compensated picture which is stored in said memory, and a subtracter 19 forming the difference between the input signals and the predicted signals which are available at the output of the circuit 18 (these predicted signals are also applied to a second input of the adder 8) so as to apply only the difference between these signals to the coding channel and to treat in this channel only these differences while taking the motion between the predicted picture (based on the preceding picture) and the input picture (or current picture) into account.
The pictures of the type P or B are predicted by estimating the shift(s) within the pictures with respect to the comparison picture(s) by means of motion vectors which are also transmitted in the data stream (most frequently in a differential manner with respect to a motion vector which has already been transmitted). This motion estimation, which is based on the luminance information components, consists of projecting the current block (or macroblock) for which the motion must be evaluated in the comparison image(s) and to compare it (or them) with all the possible blocks (macroblocks) within a search window which limits the maximum possibilities of the motion estimator. The block (macroblock) estimated in the current picture is that of the comparison picture(s) which, in a certain neighbourhood, is the most similar by correlation, the best possible correspondence generally being defined in accordance with a criterion of minimum distortion such as, for example the search to obtain the lowest possible sum of the differences between the luminances of the pixels of the two blocks or macroblocks (the criterion being referred to as MAE--Mean Absolute Error--criterion).
Various documents such as, for example patent application EP-0 560 577 or the article "Adaptive frame/field motion compensated video coding" by A. Puff, R. Aravind and B. Haskell, which appeared in "Signal Processing", vol. 5, nos. 1-2, February 1993, pp. 39-58 published by the European Association for Signal Processing (EURASIP) describe the principles of such a motion estimation and also of motion compensation which is effected at the decoding end on the basis of motion vectors thus defined, and then transmitted and/or stored. As indicated in these documents, the presence of lines from two television picture fields is exploited in the blocks (or macroblocks) under consideration, and the two motion estimation modes are defined: a frame mode and a field mode, which contributes to a realisation of the motion estimation circuit as shown in FIG. 3.
In this Figure, the motion estimation is realised in two channels, a channel 10 for searching the optimum frame vector and a channel 20 for searching the possible optimum field vectors. In each channel the motion estimation is realised in two stages: first, a search of the entire optimum motion vector(s), then a more local search of an improved vector to within half a pixel. Finally, a comparison of the motion vectors thus obtained provides the possibility of selecting one of them as being the most representative of the motion of the current block (macroblock).
More particularly, the channel 10 comprises to this end a stage 100 for searching the frame vector. Such a stage comprises, for example memories which are arranged in series and a block matching correlator. Such a correlator, which is of the conventional type and is described, for example in the document "Displacement measurement and its application in interframe image coding", by J. R. Jain and A. K. Jain, published in "IEEE Transactions on Communications", vol. COM-29, no. 12, December 1981, pp. 1799-1808, has for its object to select a motion vector to which a minimum approximation error corresponds after a search of all the possible vectors in the adopted search range. This block matching search is slightly different as the picture is of the type P or of the type B. If a picture of the type P is used, the estimated block (macroblock) is obtained from another block (macroblock) of the comparison picture, taking into account the motion which is defined by the optimum frame vector. If a picture of the type B is used, the estimated block (macroblock) is the average of the two blocks (macroblocks) obtained in a similar manner from a block (macroblock) of the previous picture and a block (macroblock) of the subsequent picture.
The stage 100 for searching the frame vector is followed by a circuit 130 for refining the search to within half a pixel, for example a symmetrical spatial interpolation filter as indicated in the cited document in "Signal Processing", February 1993. With respect to the position of a pixel resulting from the estimation before refinement, this refinement to within half a pixel takes into account the eight neighbouring positions to within half the pixel surrounding this pixel. If S is the luminance and (x,y) are the horizontal and vertical coordinates of said pixel, we have, for example: EQU S(x+0.5; y)=(S(x; y)+S(x+1; y))/2 (1) EQU S(x; y+0.5)=(S(x; y)+S(x; y+1))/2 (2) EQU S(x+0.5; y+0.5)=(S(x; y)+S(x+1; y)+S(x; y+1)+S(x+1; y+1))/4(3)
The reference V.sub.0 denotes this selected frame vector after refinement of the search, and the nature of the output signal of circuit 130 will hereinafter be indicated.
The channel 20 for searching the possible optimum field vectors comprises a stage 200 for searching field vectors including two sub-stages 210 and 220 for searching the field vector of a structure which is similar to that of the stage 100 (memories and block or macroblock-matching correlator). For this search of the optimum field vectors, two block-matching searches are performed, one for the block (macroblock) comprising the lines of a field having a given parity (i.e. twice fewer lines than in the case of stage 100), and the other for the block (macroblock) comprising the lines of the field of opposite parity. For each field, the reference block (macroblock) may be found either in the even field or in the odd field of the reference frame. As in the case of channel 10, the sub-stages 210 and 220 of the stage 200 are followed by circuits 230 and 240 for refining the search to within half a pixel. These circuits 230 and 240 have a structure which is identical to that of the circuit 130 and the references V.sub.1 and V.sub.2 denote the field vectors which can be selected (for the odd and even fields, respectively).
Finally, a decision circuit 250 receiving, in parallel, the three outputs of the circuits 130, 230, 240 for refining the search to within half a pixel, provides the possibility of choosing between frame coding or field coding, for example by comparing in these different cases and in accordance with the same criterion as hereinbefore (criterion of minimum distortion), the sums of the differences between luminances of the pixels of the blocks (macroblocks) concerned and by choosing that vector from the three vectors V.sub.0, V.sub.1, V.sub.2 for which this sum is the smallest. In the present case, the signals present at said three outputs of the circuits 130, 230, 240 are thus said sums corresponding to the three vectors V.sub.0, V.sub.1, V.sub.2, respectively, and they are indicated in FIG. 3 by the references S(V.sub.0), S(V.sub.1), S(V.sub.2), respectively. Similarly, the outputs of the stage 100 and the sub-stages 210 and 220 are denoted by S(U.sub.0), S(U.sub.1), S(U.sub.2), respectively, in which U.sub.0, U.sub.1, U.sub.2 are the frame and field vectors selected before refinement of the search and respectively corresponding to these sums.
In the motion estimation circuit of FIG. 3, the stages 100 and 200 are however the most expensive because of their complexity.

Motion estimation using half-pixel refinement of frame and field vectors


A combined mode and temperature control valve for an HVAC housing includes a cylindrical sleeve rotatable within a stationary barrel. Hot or cold air enters lengthwise inlet slots in one side of the barrel located below or above a stationary dividing baffle in the housing. Air entering the barrel can exit to either a heater outlet, defroster outlet, or A/C outlet. The sleeve includes slots and openings which, when rotated continuously through a predetermined increment, open and close the hot and cold inlets in complementary fashion to allow in a full temperature range of hot or cold air, which mixes inside the hollow cylinder. The sleeve opens only one outlet at a time, blocking the other two, over the increment of rotation.

Vehicle air conditioning system is a term used broadly enough to encompass both heating and cooling of interior air, as well as ventilation and defrosting of windshields. A typical system incorporates an evaporator core connected to a compressor and a heater core connected to the radiator, both secured inside a box like housing. Most commonly, the evaporator core is situated just behind the fresh air intake, and in front of the heater core. Therefore, all fresh air drawn into the system passes through the evaporator core first, regardless of whether the system is in a cooling or heating mode. In the heating mode, no refrigerant circulates in the evaporator core, so there is no cooling of the air even though it passes through it. While heated radiator coolant circulates continually in the heater core, a door within the housing controls temperature by deflecting air either totally or partially away from the heater core. At least two other movable doors are also needed within the housing for so called mode control, that is, for directing air into physical ducts that empty onto the windshield, toward the floor, or more directly at a vehicle occupant. These doors all need separate controls and actuators, which consumes space, has additional part count, and assembly cost.


The present invention provides for very fast detection of gaze direction using retro-reflected light from the ocular fundus that is cost-efficient, small, and portable. These eye trackers are useful in many areas of science and technology, including but not limited to remote control, space, defense, medical and psycho-physiological applications, to identify for example subtle neurologic deficits that occur with cerebellar or vestibular disorders, Parkinson's disease, strokes, traumatic brain injury, possible concussions during sports matches, some forms of reading disability, or simply fatigue or inebriation. In ophthalmology, with two such devices operating simultaneously, the variability of relative eye alignment over time can be measured, without requiring individual calibration, and without requiring fixation on a specified target, ideal for use with small children. Such instruments have widespread application as noninvasive screening devices in infants and young children or patients of any age for defects of binocular function such as strabismus and amblyopia.

With advances in user interface technologies and computer-based medical diagnostic methods, there is an increasing demand for accurate, fast, portable and inexpensive eye trackers and fixation monitors. Because eye gaze is a strong indication for current attention and intention, such devices may automatically and accurately estimate: where the person is looking, the current and past areas of attention, the possible intentions and/or the possible neurological stability of a person. Eye tracking thus provides a key input to enable a range of applications and devices that would benefit from utilizing such information. The scope of potential applications is extensive, ranging from medical diagnostics to intuitive and fast man-machine interfacing. Examples include mobile devices, computer interaction in professional environments, security applications, vehicle security and vehicle interaction, air traffic control, computer gaming, etc. Presently, eye tracking already provides great value in commercial and research-related applications such as psychology and vision research, assistive technology, eye-based communication for people with highly limited mobility, commercial usability, and advertising studies, etc.
Gaze direction can be estimated by a variety of techniques, each of them having its advantages and limitations. Most contemporary eye trackers detect eye position, usually employing the reflection of a point light source from the front surface of the cornea (corneal light reflex) relative to the bright or dark pupil (when the eye rotates, the pupil moves about twice as fast as the corneal light reflex, with the differential being a function of the direction and amount of eye movement), or relative to the reflection of the same point light source from the back of the crystalline lens of the eye (fourth Purkinje image).
More precise are the foveal eye trackers. When an individual looks at a target, that target is imaged on the fovea. It is thus foveal fixation that correlates precisely with gaze direction. It has also been shown that landmarks such as the fovea and the optic disc can be detected robustly by measuring the amount of polarization change caused by the surrounding birefringent nerve fibers during double passage of a beam of light through them upon fundus reflection in double-pass systems. Recent research has shown that techniques that effectively track or monitor the optical projection of fundus landmarks out from the eye afford a more direct measurement of fixation direction, and are physiologically more relevant. The major advantage of this new eye-fixation detection and tracking method is that it uses true information coming directly from retinal landmarks, as opposed to existing eye-tracking systems that use reflections from other structures, to identify the direction of foveal gaze.
Current non-invasive video eye trackers use digital, image-based sensors and can be relatively fast and accurate. Among them are the EyeLink 1000 Plus of SR Research (2 kHz max, after a costly upgrade from 1000 Hz), EYE-TRAC 7 of Applied Scientific Laboratories (360 Hz max), TX300 of Tobii (300 Hz max), 3D ETD of Chronos Vision GmbH (400 Hz), Hi-Speed 500 from SensoMotoric Instruments (500 Hz), and others. Yet, they are laboratory instruments that cost tens of thousands of dollars and are either cumbersome tabletop units or delicate, head-mounted devices, unsuitable for use in many patients, especially in children. For many applications in ophthalmology, neurology, otology, and neuro-otology, measurement speeds of several thousand measurements per second are highly desirable, often for an extended period of time, i.e. a minute or more. Example are studying saccades, post-saccadic oscillations, fixation stability with age-related macular degeneration, pursuit eye movement, etc. Acquiring complete digital images at a high frame rate inevitably puts a restriction on the recording time and the throughput of the system. Today, such speed without high bandwidth streaming video can only be provided by the more invasive scleral search coil recordings, which require the subject to sit within a metal antenna frame while a coil of wire is placed on the eye for measurement under exacting conditions. Scleral search coils induce discomfort and impact the eye movement and the ability to maintain convergence. Children cannot tolerate scleral search coils.
All existing eye-tracking instruments are designed to determine and track the direction of gaze of one or both eyes, requiring cooperation by the subject for precise calibration. They usually record the accuracy of fixation on a directed target.
A method and device are therefore needed for fast and accurate eye tracking and fixation monitoring, without requiring digital streaming, storage and manipulation of complete images at high frame rates, but rather acquisition and transmission of only sufficient data needed for X-Y tracking of the pupil.


Solid particulates are removed from a solid particulate-laden fluid stream by passing the solid particulate laden fluid stream into a potential flow centrifugal separator which splits the potential solid particulate-laden fluid stream into a clean fluid stream and a concentrated solid particulate-laden fluid stream, passing the concentrated solid particulate-laden fluid stream into a solids collector which extracts solid particulates from the concentrated solid particulate-laden fluid stream leaving a fluid stream having a reduced solid particulate content, and conducting the fluid stream having a reduced solid particulate content back into the potential flow centrifugal separator for further processing.

The present invention relates generally to materials treatment and more particularly to a method and apparatus for mechanically removing solid particulates from a fluid stream.
The discipline of separation and purification of solid materials is concerned with development and application of methods and processes in comminution, sorting and concentration or enrichment of primary or secondary raw materials. It encompasses a wide variety of processes including: crushing and milling, screening, sorting, classification, and separation of multiphase and multicomponent systems. The basic processes considered here include solid-gas, solid-liquid, and solid-solid-liquid systems.
Separation of solid particulates from gases or liquids depends on subjecting particles to a certain force which drives them to a collecting surface. The forces may be gravitational, inertial, physical or barrier, or diffusional. One mechanical type device that is commonly used to separate solid particulates from fluids is the cyclone collector. The cyclone collector operates on a centrifugal principle and is widely used for classification and for performing separations in solids-laden gases or slurries. In a cyclone collector the dirty feed stream enters through a tangential inlet into a cylindrical section, setting up a rotational motion and forming a vortex along the inside surface between the underflow and overflow. The stream is fed at sufficiently high velocity so that the centrifugal forces along the walls cause the particles to settle against the walls where they are directed to the underflow. Coincidentally, some fine particles can pass into a secondary vortex and out through the overflow.
Cyclone efficiency, defined at the underflow for each size fraction, can approach 100 percent for coarse particles and 0.0 percent for very fine sizes. Cyclone performance can be reliably predicted in most applications. However, its practical use is restricted to certain operating limits which must be maintained. One such limitation occurs when the solids are too small. Usually when the solids are less than 5 or 10 microns in diameter, separation efficiency for most materials is unsatisfactory. Another limit is that of the fluid and solids density. For good performance, the differential between solids and fluids specific gravities must be sufficient for good separation. Finally, highly viscous fluids do not produce sharp separations.
The present invention relates to an improved method and apparatus for removing very small particulates.
In U.S. Pat. No. 3,257,798 there is disclosed an exhaust treatment apparatus which includes a first cyclonic separator and a second cyclonic separator. The first cyclonic separator divides an exhaust gas mixture into a clean stream and a dirty stream while the second cyclonic separator removes solid particulates from the dirty gas stream emitted from the first cyclonic separator. The clean gas streams from both cyclonic separators are fed into a catalytic converter where they are purified and then exhausted.
In U.S. Pat. No. 3,254,478 there is disclosed a dust collecting apparatus which includes a cyclone type device and wherein the separated gas stream is recycled by an exhauster back to the inlet opening in the cyclone type device.
In U.S. Pat. Nos. 4,001,121, 4,298,359 and 4,460,391 there are disclosed tangential inertial separators wherein the clean gas is removed from the center of the cyclone vortex while the remaining gas and separated solids are exhausted tangentially for further cleanup.
Other known patents of interest are U.S. Pat. Nos. 1,660,865, 1,845,358, 1,845,567, 2,701,056, 2,818,935, 3,095,369 and 3,948,771. In FIGS. 20-103(b) on page 20-87 of Perry's Chemical Engineer Handbook, Fifth Edition, there is shown a mechanical collector with recirculating flow. The collection efficiency of this unit is comparable with that of a cyclone. The centrifugal fields are higher than in a cyclone, but this is compensated by the higher intensity of the secondary flows, with their inherent reentrainment tendencies.
It is an object of this invention to provide a new and improved method and apparatus for removing solid particulates from a fluid stream.
It is another object of this invention to provide a new and improved method and apparatus for removing solid particulates from a fluid stream using inertial type devices.
It is a further object of this invention to provide a method and apparatus for removing solid particulates from a fluid stream using inertia type devices and which has a high separation efficiency, even for submicron size particles.

Potential flow centrifugal separator system for removing solid particulates from a fluid stream


A method for transmitting signals, consisting of receiving a plurality of signals generated in an isolated region, the signals encoding respective individual payloads and payload envelopes. At least two of the signals operate under different protocols. The method includes deriving information from the signals on respective connections of the signals, and aggregating the payloads into one or more aggregated payloads. The method further includes transmitting the one or more aggregated payloads and the information via a satellite link to a receiver outside the region, the one or more aggregated payloads and the information amounting to less data than an aggregated amount of data in the individual payloads and payload envelopes. The method also includes reconstituting the plurality of signals at the receiver using the one or more aggregated payloads and the information.

In passenger aircraft, there is typically a large number of different types of wireless signals originating from, and being directed to, the passengers and/or crew. Some of these signals are internal to the aircraft, but typically most are between the aircraft and an entity external to the aircraft. The signals may be classified as voice communications, or as data communications.
Both types of communication are typically transmitted as packets using various protocols such as the Internet Protocol (IP), the User Datagram Protocol (UDP), the Transmission Control Protocol (TCP), and/or the Real-Time Transport Protocol (RTP). These protocols are respectively described in Request For Comments (RFC) documents RFC 791, RFC 768, RFC 793, and RFC 1889, which may be found at www.faqs.org/rfcs/, and which are incorporated herein by reference. Voice communications are also transmitted using specific cellular telephone protocols, such as a Code Division Multiple Access (CDMA) protocol, a global system for mobile (GSM) protocol, and/or various orthogonal frequency division multiplexing (OFDM) protocols.
The communications external to the aircraft are typically transmitted via links which are limited in bandwidth, and the bandwidth limitation causes problems, such as dropped data connections, long voice call setup times, and reduced voice quality. While some solutions to the problems caused have been found, for example, the application of a differentiated services architecture, the solutions are at best partial fixes for the problems.
Thus, an improved method for transmitting traffic from an isolated system such as an aircraft cabin would be advantageous.

Traffic optimization in a heterogeneous wireless cabin network


A sun visor assembly comprises a support rod displaceable between a first position, extending along a windshield, and a second position extending along a side window. A visor body is carried on the support rod. A cam is configured to displace the visor body along the support rod from a home position to an extended position as the support rod is displaced toward the second position. A sun visor operating method and method of educating an operator with respect to a capability of a visor body to slide along a support rod are also disclosed.

Sun visors are installed in motor vehicles in an effort to shield the driver and passenger's eyes from sunlight that might otherwise interfere with the chosen sight path outside the motor vehicle. Typically, a sun visor assembly includes a sun visor that is displaceable between a stowed position resting against the headliner of the motor vehicle, a first deployed position resting adjacent a windshield of the motor vehicle to shield sunlight directed through the windshield and a second deployed position resting along the side window of the motor vehicle to shield sunlight directed though the side window.
Toward this end, a sun visor assembly typically includes a support rod that may be pivoted between a first position, extending along the windshield and a second position, extending along the side window as well as a visor body that may be rotated about the support rod. In some embodiments, the visor body may include yet another degree of freedom allowing the visor body to slide along the length of the support rod. This allows one to extend the visor body to reach across the side window glass toward the B pillar of the motor vehicle when the visor body is in the second deployed position. This lengthwise adjustment often allow the user to position the visor body more effectively for screening the eyes from sunlight through the side window.
This document relates to a new and improved sun visor assembly incorporating a built-in or integral cam configured to displace the visor body along the support rod from a home position to an extended position when the support body is displaced toward the second position. This positions the visor body in a better position to more effectively screen and shield the eyes of the operator from sunlight coming through the side window while also effectively educating the operator with respect to the capability of the visor body to slide along the support rod. This latter convenience feature is often unknown to a motor vehicle operator.


An improved structure is provided for supporting pillars of automotive vehicles which provides energy absorption through provision of three stamped metallic panels (24,26,28) defining first and second energy absorbing chambers (56,58) therebetween and an interior trim cover (30) joined to all the panels and defining a third chamber (62) between it and the interior of the three panels and selected energy absorbing media carried between the trim cover and the interior of the panels. Generally C-shaped spring structures (74) and plastic honeycomb structures (68) are preferred for the energy absorbing media.

1. Technical Field
The present invention relates generally to automotive vehicle body structure, and more particularly to the construction of automotive vehicle pillars to accommodate energy absorption.
2. Description of the Prior Art
In the design of modern automotive vehicles, it is has been the goal to provide body structures which manage the absorption of energy in response to the imposition of frontal loads. More recent design activity in the vehicle body arts has been directed to the management of energy imposed on the vehicle occupant compartment in response to loads imposed on the sides of the vehicle and to loading imposed within the vehicle occupant compartment. While the cushioning of surfaces facing the vehicle occupant compartment has long been practiced in the automotive industry, the basic, usually metal, structure of the body itself has been accommodated rather than made an integral part of the energy management design, although early designs, such as that exemplified in U.S. Pat. No. 3,560,020 to Barenyi, indicate the general principle of cushioning such structure is known.

Energy absorbing vehicle pillar structure