A communication system including a transmitter, a receiver, a communication link (for example, a TMDS-like link), and preferably also an external agent with which the transmitter and receiver can communicate, in which video data (or other data) are encrypted, the encrypted data are transmitted from the transmitter to the receiver, and the transmitted data are decrypted in the receiver, a transmitter and a receiver for use in such a system, a cipher engine for use in such a transmitter or receiver, a method for operating such a transmitter or receiver to encrypt or decrypt data, and a method for distributing keys to the transmitter and receiver. The receiver can be a player coupled to a downstream receiver by a TMDS-like link, and configured to re-encrypt the decrypted data (for example, using an AES or HDCP protocol) and send re-encrypted data over the link to the receiver. Optionally, the player is a repeater which translates the decrypted data from the transmitter, and then re-encrypts the translated data for transmission to the downstream receiver. The transmitter can itself be a player that receives and decrypts encrypted data from an upstream source. In preferred embodiments, the system implements a content protection protocol including a challenge-response procedure. After a new key is supplied to the receiver (and the same new key should have been supplied to the transmitter) and before the receiver can use the new key, the challenge-response procedure requires that the receiver validate the transmitter by verifying that the transmitter has proper knowledge of the new key.

There are various, well-known serial links for transmitting video data and other data. One conventional serial link is known as a transition minimized differential signaling interface ("TMDS" link). This link is used primarily for high-speed transmission of video data from a set-top box to a television, and also for high-speed transmission of video data from a host processor (e.g., a personal computer) to a monitor. Among the characteristics of a TMDS link are the following:
1. video data are encoded and then transmitted as encoded words (each 8-bit word of digital video data is converted to an encoded 10-bit word before transmission);                a. the encoding determines a set of "in-band" words and a set of "out-of-band" words (the encoder can generate only "in-band" words in response to video data, although it can generate "out-of-band" words in response to control or sync signals. Each in-band word is an encoded word resulting from encoding of one input video data word. All words transmitted over the link that are not in-band words are "out-of-band" words);        b. the encoding of video data is performed such that the in-band words are transition minimized (a sequence of in-band words has a reduced or minimized number of transitions);        c. the encoding of video data is performed such that the in-band words are DC balanced (the encoding prevents each transmitted voltage waveform that is employed to transmit a sequence of in-band words from deviating by more than a predetermined threshold value from a reference potential. Specifically, the tenth bit of each "in-band" word indicates whether eight of the other nine bits thereof have been inverted during the encoding process to correct for an imbalance between running counts of ones and zeroes in the stream of previously encoded data bits);
2. the encoded video data and a video clock signal are transmitted as differential signals (the video clock and encoded video data are transmitted as differential signals over conductor pairs without the presence of a ground line);
3. three conductor pairs are employed to transmit the encoded video, and a fourth conductor pair is employed to transmit the video clock signal; and
4. signal transmission occurs in one direction, from a transmitter (typically associated with a desktop or portable computer, or other host) to a receiver (typically an element of a monitor or other display device).
It is foreseeable that a common use for encryption will be to encrypt video data for transmission over a serial link from a set-top box to a television, and it has been proposed to encrypt video data for transmission over a TMDS serial link (e.g., from a set-top box to a television). For example, it has been proposed to use the cryptographic protocol known as the "High-bandwidth Digital Content Protection" ("HDCP") protocol to encrypt digital video data to be transmitted over the "Digital Video Interface" ("DVI" link) adopted by the Digital Display Working Group, and to decrypt the encrypted video data at the DVI receiver.
A DVI link can be implemented to include two TMDS links (which share a common conductor pair for transmitting a video clock signal) or one TMDS link, as well as additional control lines between the transmitter and receiver. We shall describe a DVI link (that includes one TMDS link) with reference to FIG. 1. The DVI link of FIG. 1 includes transmitter 1, receiver 3, and the following conductors between the transmitter and receiver: four conductor pairs (Channel 0, Channel 1, and Channel 2 for video data, and Channel C for a video clock signal), Display Data Channel ("DDC") lines for bidirectional communication between the transmitter and a monitor associated with the receiver in accordance with the conventional Display Data Channel standard (the Video Electronics Standard Association's "Display Data Channel Standard," Version 2, Rev. 0, dated Apr. 9, 1996), a Hot Plug Detect (HPD) line (on which the monitor transmits a signal that enables a processor associated with the transmitter to identify the monitor's presence), Analog lines (for transmitting analog video to the receiver), and Power lines (for providing DC power to the receiver and a monitor associated with the receiver). The Display Data Channel standard specifies a protocol for bidirectional communication between a transmitter and a monitor associated with a receiver, including transmission by the monitor of an Extended Display Identification ("EDID") message that specifies various characteristics of the monitor, and transmission by the transmitter of control signals for the monitor. Transmitter 1 includes three identical encoder/serializer units (units 2, 4, and 5) and additional circuitry (not shown). Receiver 3 includes three identical recovery/decoder units (units 8, 10, and 12) and inter-channel alignment circuitry 14 connected as shown, and additional circuitry (not shown).
As shown in FIG. 1, circuit 2 encodes the data to be transmitted over Channel 0, and serializes the encoded bits. Similarly, circuit 4 encodes the data to be transmitted over Channel 1 (and serializes the encoded bits), and circuit 6 encodes the data to be transmitted over Channel 2 (and serializes the encoded bits). Each of circuits 2, 4, and 6 responds to a control signal (an active high binary control signal referred to as a "data enable" or "DE" signal) by selectively encoding either digital video words (in response to DE having a high value) or a control or synchronization signal pair (in response to DE having a low value). Each of encoders 2, 4, and 6 receives a different pair of control or synchronization signals: encoder 2 receives horizontal and vertical synchronization signals (HSYNC and VSYNC); encoder 4 receives control bits CTL0 and CTL1; and encoder 6 receives control bits CTL2 and CTL3. Thus, each of encoders 2, 4, and 6 generates in-band words indicative of video data (in response to DE having a high value), encoder 2 generates out-of-band words indicative of the values of HSYNC and VSYNC (in response to DE having a low value), encoder 4 generates out-of-band words indicative of the values of CTL0 and CTL1 (in response to DE having a low value), and encoder 6 generates out-of-band words indicative of the values of CTL2 and CTL3 (in response to DE having a low value). In response to DE having a low value, each of encoders 4 and 6 generates one of four specific out-of-band words indicative of the values 00, 01, 10, or 11, respectively, of control bits CTL0 and CTL1 (or CTL2 and CTL3).
As noted above, it has been proposed to use the cryptographic protocol known as the "High-bandwidth Digital Content Protection" ("HDCP") protocol to encrypt digital video to be transmitted over a DVI link and to decrypt the data at the DVI receiver. The HDCP protocol is described in the document "High-bandwidth Digital Content Protection System," Revision 1.0, dated Feb. 17, 2000, by Intel Corporation, and the document "High-bandwidth Digital Content Protection System Revision 1.0 Erratum," dated Mar. 19, 2001, by Intel Corporation. The full text of both of these documents is incorporated herein by reference.
A DVI transmitter implementing the HDCP protocol asserts a stream of pseudo-randomly generated 24-bit words, known as cout[23:0], during the video active period (i.e. when DE is high). Each 24-bit word of the cout data is "Exclusive Ored" (in logic circuitry in the transmitter) with a 24-bit word of RGB video data input to the transmitter, in order to encrypt the video data. The encrypted data are then encoded (according to the TMDS standard) for transmission. The same sequence of cout words is also generated in the receiver. After the encoded and encrypted data received at the receiver undergo TMDS decoding, the cout data are processed together with the decoded video in logic circuitry in order to decrypt the decoded data and recover the original input video data.
Before the transmitter begins to transmit HDCP encrypted, encoded video data, the transmitter and receiver communicate bidirectionally with each other to execute an authentication protocol (to verify that the receiver is authorized to receive protected content, and to establish shared secret values for use in encryption of input data and decryption of transmitted encrypted data). More specifically, each of the transmitter and the receiver is preprogrammed (e.g., at the factory) with a 40-bit word known as a key selection vector, and an array of forty 56-bit private keys. To initiate the first part of an authentication exchange between the transmitter and receiver, the transmitter asserts its key selection vector (known as "AKSV"), and a pseudo-randomly generated session value ("An") to the receiver. In response, the receiver sends its key selection vector (known as "BKSV") and a repeater bit (indicating whether the receiver is a repeater) to the transmitter, and the receiver also implements a predetermined algorithm using "AKSV" and the receiver's array of forty private keys to calculate a secret value ("Km"). In response to the value "BKSV" from the receiver, the transmitter implements the same algorithm using the value "BKSV" and the transmitter's array of forty private keys to calculate the same secret value ("Km") as does the receiver.
Each of the transmitter and the receiver then uses the shared secret value "Km," the session value "An," and the repeater bit to calculate a session key ("Ks") and two values ("M0" and "R0") for use during a second part of the authentication exchange. The second part of the authentication exchange is performed only if the repeater bit indicates that the receiver is a repeater, to determine whether the status of one or more downstream devices coupled to the repeater requires revocation of the receiver's authentication.
After the first part of the authentication exchange, and (if the second part of the authentication exchange is performed) if the receiver's authentication is not revoked as a result of the second part of the authentication exchange, each of the transmitter and the receiver generates a 56-bit frame key Ki (for initiating the encryption or decrypting a frame of video data), an initialization value Mi, and a value Ri used for link integrity verification. The Ki, Mi, and Ri values are generated in response to a control signal (identified as "ctl3" in FIG. 2), which is received at the appropriate circuitry in the transmitter, and is also sent by the transmitter to the receiver, during each vertical blanking period, when DE is low. As shown in the timing diagram of FIG. 2, the control signal "ctl3" is a single high-going pulse. In response to the Ki, Mi, and Ri values, each of the transmitter and receiver generates a sequence of pseudo-randomly generated 24-bit words cout[23:0]. Each 24-bit word of the cout data generated by the transmitter is "Exclusive Ored" (in logic circuitry in the transmitter) with a 24-bit word of a frame of video data (to encrypt the video data). Each 24-bit word of the cout data generated by the receiver is "Exclusive Ored" (in logic circuitry in the receiver) with a 24-bit word of the first received frame of encrypted video data (to decrypt this encrypted video data). The 24-bit words cout[23:0] generated by the transmitter are encryption keys (for encrypting a line of input video data), and the 24-bit words cout[23:0] generated by the receiver are decryption keys (for decrypting a received and decoded line of encrypted video data).
During each horizontal blanking interval (in response to each falling edge of the data enable signal DE) following assertion of the control signal ctl3, the transmitter performs a rekeying operation and the receiver performs the same rekeying operation to change (in a predetermined manner) the cout data words to be asserted during the next active video period. This continues until the next vertical blanking period, when the control signal ctl3 is again asserted to cause each of the transmitter and the receiver to calculate a new set of Ki and Mi values (with the index "i" being incremented in response to each assertion of the control signal ctl3). The Ri value is updated once every 128 frames. Actual encryption of input video data (or decryption of received, decoded video data) is performed, using the cout data words generated in response to the latest set of Ks, Ki and Mi values, only when DE is high (not during vertical or horizontal blanking intervals).
Each of the transmitter and receiver includes an HDCP cipher circuit (sometimes referred to herein as an "HDCP cipher") of the type shown in FIG. 3. The HDCP cipher includes linear feedback shift register (LFSR) module 80, block module 81 coupled to the output of LFSR module 80, and output module 82 coupled to an output of block module 81. LFSR module 80 is employed to re-key block module 81 in response to each assertion of an enable signal (the signal "ReKey" shown in FIG. 3), using the session key (Ks) and the current frame key (Ki). Block module 81 generates (and provides to module 80) the key Ks at the start of a session and generates (and applies to module 80) a new value of key Ki at the start of each frame of video data (in response to a rising edge of the control signal "ctl3," which occurs in the first vertical blanking interval of a frame). The signal "ReKey" is asserted to the FIG. 3 circuit at each falling edge of the DE signal (i.e., at the start of each vertical and each horizontal blanking interval), and at the end of a brief initialization period (during which module 81 generates an updated value of the frame key Ki) after each rising edge of signal "ctl3."
Module 80 consists of four linear feedback shift registers (having different lengths) and combining circuitry coupled to the shift registers and configured to assert a single output bit per clock interval to block module 81 during each of a fixed number of clock cycles (e.g., 56 cycles) commencing on each assertion of the signal "ReKey" when DE is low (i.e., in the horizontal blanking interval of each line of video data). This output bit stream is employed by block module 81 to re-key itself just prior to the start of transmission or reception of each line of video data.
Block module 81 comprises two halves, "Round Function K" and "Round Function B," as shown in FIG. 4. Round Function K includes 28-bit registers Kx, Ky, and Kz, seven S-Boxes (each a 4 input bit by 4 output bit S-Box including a look-up table) collectively labeled "S-Box K" in FIG. 4, and linear transformation unit K, connected as shown. Round Function B includes 28-bit registers Bx, By, and Bz, seven S-Boxes (each a 4 input bit by 4 output bit S-Box including a look-up table) collectively labeled "S-Box B" in FIG. 4, and linear transformation unit B, connected as shown. Round Function K and Round Function B are similar in design, but Round Function K performs one round of a block cipher per clock cycle to assert a different pair of 28-bit round keys (Ky and Kz) each clock cycle in response to the output of LFSR module 80, and Round Function B performs one round of a block cipher per clock cycle, in response to each 28-bit round key Ky from Round Function K and the output of LFSR module 80, to assert a different pair of 28-bit round keys (By and Bz) each clock cycle. The transmitter generates value An at the start of the authentication protocol and the receiver responds to it during the authentication procedure. The value An is used to randomize the session key. Block module 81 operates in response to the authentication value (An), and the initialization value (Mi) which is updated by output module 82 at the start of each frame (at each rising edge of the control signal "ctl3").
Each of linear transformation units K and B outputs 56 bits per clock cycle. These output bits are the combined outputs of eight diffusion networks in each transformation unit. Each diffusion network of linear transformation unit K produces seven output bits in response to seven of the current output bits of registers Ky and Kz. Each of four of the diffusion networks of linear transformation unit B produces seven output bits in response to seven of the current output bits of registers By, Bz, and Ky, and each of the four other diffusion networks of linear transformation unit B produces seven output bits in response to seven of the current output bits of registers By and Bz.
In Round Function K, one bit of register Ky takes its input from the bit stream asserted by module 80 when the ReKey signal is asserted. In Round Function B, one bit of register By takes its input from the bit stream asserted by module 80 when the ReKey signal is asserted.
Output module 82 performs a compression operation on the 28-bit keys (By, Bz, Ky and Kz) asserted to it (a total of 112 bits) by module 81 during each clock cycle, to generate one 24-bit block of pseudo-random bits cout[23:0] per clock cycle. Each of the 24 output bits of module 82 consists of the exclusive OR ("XOR") of nine terms as follows: (B0*K0)+(B1*K1)+(B2*K2)+(B3*K3)+(B4*K4)+(B5*K5)+(B6*K6)+(B7)+(K7), where "*" denotes a logical AND operation and "+" denotes a logical XOR operation. FIG. 5 specifies the input values B0-B7 and K0-K7 in the preceding expression for generating each of the 24 output bits of module 82. For example, FIG. 5 indicates that in order to generate output bit 0 (i.e., cout(0)), B0 is the seventeenth bit of register Bz, K0 is the third bit of register Kz, B1 is the twenty-sixth bit of register Bz, and so on.
In the transmitter, logic circuitry 83 (shown in FIG. 3) receives each 24-bit word of cout data and each input 24-bit RGB video data word, and performs a bitwise XOR operation thereon in order to encrypt the video data, thereby generating a word of the "data_encrypted" data indicated in FIG. 3. Typically, the encrypted data subsequently undergoes TMDS encoding before it is transmitted to a receiver. In the receiver, logic circuitry 83 (shown in FIG. 3) receives each 24-bit block of cout data and each recovered 24-bit RGB video data word (after the recovered data has undergone TMDS decoding), and performs a bitwise XOR operation thereon in order to decrypt the recovered video data.
Throughout the specification and in the claims the expression "TMDS-like link" will be used to denote a serial link, capable of transmitting digital video data (and a clock for the digital video data) from a transmitter to a receiver, and optionally also transmitting one or more additional signals (bidirectionally or unidirectionally) between the transmitter and receiver, that is or includes either a TMDS link or a link having some but not all of the characteristics of a TMDS link.
There are several conventional TMDS-like links. One type of TMDS-like link is the set of serial links known as Low Voltage Differential Signaling ("LVDS") links (e.g., "LDI," the LVDS Display Interface), each of which satisfies the TIA/EIA-644 standard or the IEEE-1596.3 standard. In each system including an LVDS link, the data are sent on a high-speed differential link with a synchronous clock. There is a single clock line with a four to three duty cycle and several different combinations of data lines depending on the data rate and bit depth. An LVDS link is a serial and differential video link, but the video data transmitted over an LVDS link is not encoded.
Other TMDS-like links encode input video data and other data to be transmitted into encoded words comprising more bits than the incoming data using a coding algorithm other than the specific algorithm used in a TMDS link, and transmit the encoded video data as in-band characters and the other encoded data as out-of-band characters. The characters need not be classified as in-band or out-of-band characters based according to whether they satisfy transition minimization and DC balance criteria. Rather, other classification criteria could be used. An example of an encoding algorithm, other than that used in a TMDS link but which could be used in a TMDS-like link, is IBM 8b10b coding. The classification (between in-band and out-of-band characters) need not be based on just a high or low number of transitions. For example, the number of transitions of each of the in-band and out-of-band characters could (in some embodiments) be in a single range (e.g., a middle range defined by a minimum and a maximum number of transitions).
The data transmitted between the transmitter and receiver of a TMDS-like link can, but need not, be transmitted differentially (over a pair of conductors). Although the differential nature of TMDS is important in some applications, it is contemplated that some TMDS-like links will transmit data other than differential data. Also, although a TMDS link has four differential pairs (in the single pixel version), three for video data and the other for a video clock, a TMDS-like link could have a different number of conductors or conductor pairs.
The primary data transmitted by a TMDS link are video data. What is often significant about this is that the video data are not continuous, and instead have blanking intervals. However, many TMDS-like serial links do not transmit data having blanking intervals, and thus do not encode input data (for transmission) in response to a data enable signal. For example, the audio serial links known as I2S and S/PDIF transmit continuous data.
We shall refer to content protection protocols other than the HDCP protocol as "non-HDCP" protocols. Not only content protection protocols that closely resemble the HDCP protocol (but differ therefrom in one or more respects), but also content protection protocols very different from the HDCP protocol, shall be referred to as "non-HDCP protocols."
Aspects of the present invention employ (or are useful in implementing) encryption and/or decryption of data in accordance with the HDCP protocol, or non-HDCP protocols that are modified versions of the HDCP protocol in which the transmitter and receiver obtain the shared secret value ("Km"), directly or indirectly, from an external agent. Other aspects of the present invention employ (or are useful in implementing) encryption and/or decryption of data in accordance with other non-HDCP protocols.
Some embodiments of the invention contemplate that encrypted data is transmitted over a serial link. Other embodiments do not require that encrypted data are transmitted over a serial link. Examples of serial links include the above-mentioned DVI, TMDS, and TMDS-like links, ethernet links, fiberchannel links, serial ATA links used by disk drives, and others.

Method and system for encrypting and decrypting data using an external agent


One example of an engine mounted inlet plenum for a rotorcraft includes an inlet flange, an outlet flange and a plenum duct that connects the inlet flange and the outlet flange. The inlet flange, which defines an inlet to flow air into a barrier filtration system, is configured to be substantially aligned with a closed cowl door assembly of the rotorcraft. In some implementations, the plenum duct is configured to extend to an outer mold line (OML) of the rotorcraft such that the inlet flange is aligned with the OML. The outlet flange defines an outlet to flow air filtered by the barrier filtration system into an engine of the rotorcraft. The plenum duct allows air to flow from the inlet to the outlet.

Some rotorcrafts include cowling assemblies configured to act as a protective fairing around the engine and other propulsion related components. Certain rotorcraft configurations can include an engine housed in a nacelle which acts as an aerodynamic pod for the engine. The nacelle configuration can be implemented when the engine is located at a distance from the fuselage, such as on a wing of the rotorcraft. Inlet systems can be used to provide an aerodynamic flow path from the exterior of the cowl door assembly (or nacelle) to the engine inlet. In some configurations, filtration systems can be installed in the inlet systems.

Engine mounted inlet plenum for a rotorcraft


Systems and methods for effectuating transparent transaction processing takeover in a communications system. An active queue computer facilitates the processing of transactions from a first network layer using an internal active queue. One or more stand-by queue computers shadow the processing of the active queue computer by maintaining internal stand-by queues that are continually synchronized with the active queue. Upon detecting that the active queue computers has entered a failure state, a stand-by queue computer takes over the processing of pending transactions, preferably including those that are currently in the active and stand-by queues. The stand-by computer, now in pseudo-active mode, may return active processing to the former active queue computer after rebooting, may request a network address change to takeover active processing on the stand-by queue computer, or may facilitate the transferring of active status to an additional computer.

1. Field of the Invention
The present invention generally relates to fault tolerant network systems, and, more specifically, the present invention relates to an active/pseudo-active/stand-by queue computer system in which transparent request processing takeover is enabled in the case of a software and operating system failure in an active queue computer.
2. Description of the Background
As computer networks become more prevalent in everyday life, the number of both business and personal activities that rely on such methods has increased dramatically. Generally speaking, in a typical network environment, there are a plurality of client computers (users) that issue requests to a plurality of application servers (AP servers) that process those requests. The client computers and AP servers are referred to as existing on the client server layer and the AP server layer, respectively, with the interconnection points on the system known as nodes.
Because so many different computers or other equipment are connected to a single network, the system must have a way in which one machine can communicate with another machine in an efficient way. Because a direct communication link from every computer and/or piece of equipment to every other computer would be costly, networks typically allow for some type of shared communication. The most popular type of network communication scheme involves assigning each machine connected to the network a unique address, and then sending information back and forth across the network in discrete units of information (e.g., "packets") that carry the address of both the sending computer ("sender") and the receiving computer ("receiver"). In this way, each machine can identify information that is addressed to it, and respond accordingly. One popular protocol for such a communication procedure is TCP/IP (Transaction Control Protocol/Internet Protocol).
Each machine on the network physically interconnects with the wired or wireless communication medium via a network interface card or "NIC." Every NIC has a machine address (MAC) that is a unique identifier of that machine. TCP/IP packets that travel throughout a network contain not only data but also address information including the IP address (actual or alias) and the MAC address of both the sending and the receiving computers. The NIC browses all of the packets that travel throughout the network searching for packets that contain its own MAC/IP address. If the NIC determines that a packet contains its own address as the destination, the NIC will receive the entire packet. Likewise, if a packet does not include the NIC's address, the packet will generally be ignored by the NIC.
A NIC may also have a "promiscuous mode" in which all packets are received. If the promiscuous mode is set for a NIC, all packets are received by the NIC without determining whether or not the packet includes that NIC's MAC address. This process of receiving all packets is known as "sniffing" all of the packets on the network. This process may useful in the design of fault tolerant systems.
As mentioned above, every TCP/IP packet that travels throughout a system includes the IP address and the MAC address of both the sender and the intended receiver of the packet. These IP and MAC addresses are added by a network driver running on the sending computer with a NIC installed therein. In some fault tolerant systems, the "sending" IP address and MAC address are set by the NIC so as to reflect the IP and MAC addresses of a machine other than that which actually sends the packet. Through this process, the NIC which receives the packet with the "incorrect" IP and MAC address information will not respond to the computer who sent the packet (because it will not have that computer's proper addresses). This process is known as "spoofing" the packets, and any reply to such a spoofed packet will be sent to the spoofed machine. This technique is often used by hackers who do not wish to be identified.
In order to communicate with another machine over a TCP/IP network, a packet sending computer needs to know the IP address and the MAC address of a receiving computer. The method for determining the correspondence between a NIC's MAC address and the IP address is known as Address Resolution Protocol (ARP). To determine a host B's MAC address, host A sends out an ARP request for the hardware address of host B. Host B sees the request on the network and sends an ARP reply containing the hardware address for the interface with the IP address in question. Host A then records the hardware address in its ARP cache for future use in sending TCP/IP packets.
There is also a similar process known as a gratuitous ARP request. A gratuitous ARP is an ARP reply that is sent by a host even when no ARP request is made to that host. A gratuitous ARP reply is typically addressed to the broadcast hardware address so that all hosts on the local area network (LAN) will receive the ARP reply. Upon receipt of the gratuitous ARP reply, all hosts on the network refresh their ARP cache to reflect the gratuitous ARP. Gratuitous ARP is generally used when the relationship between an IP address and a MAC address changes, i.e., when an IP takeover occurs. With the gratuitous ARP, the change can be communicated to all other hosts on the system in an efficient manner, so that future communications reflect the change.
Because these network communication schemes are so complex, it is often difficult to determine whether or not a certain machine or a certain node on the network is not functioning properly. Because a machine may be engaging in many simultaneous communications with different computers, it may also be difficult to track when these errors occur. Additionally, when an error occurs in a network machine, the other machines must either be made aware of this error (failure state), or some background process must be undertaken to correct the error without the knowledge of the other computers on the network. Such a correction procedure is considered "transparent" to the other computers.
The general category of these error correction or mitigation systems is known as fault tolerant processing. One of the main problems to be addressed by fault tolerant processing is the taking over by another computer (either temporarily-or permanently) of the operations of one computer which enters a fault state. Traditionally, this takeover can only occur in either a limited fashion, or with some disruption caused to the users or client computers (i.e., it is not transparent). Some of the more recent fault tolerant systems are now described.
Japanese Patent Publication No. 11-296396 entitled "Widely Applicable System With Changeover Concealing Function" generally describes a fault recovery system including an active system host and a stand-by system host. Each of these hosts has an associated NIC attached thereto, and each of the hosts is also attached to the NIC of the other system host (active host to stand-by NIC and stand-by host to active NIC). If a system failure occurs in the active system, the stand-by system host will use the NIC of the active system host (via the direct connection), and then MAC address and IP takeover may be achieved.
This system is undesirable to implement because it requires the use of additional hardware (the host/NIC interconnections). Additionally, if the failure error occurs on the active host NIC, rather than on the active host itself, this system is unable to perform the requisite MAC address takeover. Finally, this system is limited in that only MAC address takeover occurs. Any transactions that are being processed during the time when the active host system enters failure mode will be lost, and cannot be recovered to be executed by the stand-by host.
U.S. Pat. No. 6,049,825 entitled "Method and System for Switching Between Duplicated Network Interface Adapters for Host Computer Communications" generally describes a method for switching between duplicated network adapters to provide some level of fault tolerance. This system uses a gratuitous ARP to enable NIC takeover upon detection of a fault.
This type of gratuitous ARP method is not preferred because it is not transparent to the client. In others words, the client computers are aware of the fault. Additionally, because the NIC takeover occurs because of the gratuitous ARP process, the takeover takes an undesirable amount of time for completion. Finally, in a similar problem to that discussed in the above case, this system only provides for NIC takeover, and any transaction that is currently being processed during the time of the fault's occurrence will be lost and must be re-sent by the client.
Japanese Patent Publication No. 2000-056996 entitled "Decentralized Queue System" generally describes a method in which a plurality of queues, that are communicatively connected to each other, are interspersed between several client computers and several application servers. A client request is en-queued in a first queue, and the request is then additionally en-queued into a second queue before the client sends out a second request to the queues. If a fault occurs in the first queue during processing of the request, the second queue is capable of sending the request to the application servers for processing (as well as potentially copying the request to yet another queue in case of a fault in the second queue).
Initially, this method is not satisfactory for communications systems that rely on the speed of data travel because of the large amount of overhead involved in passing every request to more than one queue. Also, although this method somewhat lessens the chance of losing a request, it does not accomplish an IP takeover procedure. Finally, once a queue fails, the connection between the queue system and the server is lost, and the clients must be made aware of the error to re-route future packets—all of which creates even more overhead.
Japanese Patent Publication No. 10-135993 entitled "Address-Setting System in Duplicate System" generally provides a system capable of performing MAC address and IP address takeover. The system includes an address buffer that stores a plurality of MAC addresses. If a system failure occurs, a stand-by computer performs an IP takeover using an alias IP address and MAC takeover using this address buffer. A system rebooting process for the originally active computer (now in stand-by) can test if the network environment is functioning normally by using the original IP address and MAC address.
Although this system is capable of performing MAC address and IP address takeover, it is not capable of addressing any of the requests that are currently being processed by the host when a failure occurs. Again, these requests are lost unless and until they are resent by the client. Also, the above MAC address and IP address processes are not efficient—these takeover processes take an extended period of time to perform.
Japanese Patent Publication No. 2000-322350 entitled "Server Switching System For Client Server System" generally describes a system for rerouting requests to bypass servers that have encountered a failure. The system includes a switching mechanism inserted between a client and a plurality of application servers. All requests from the client to the application servers pass through this switching mechanism so that, if a failure occurs in one of the application servers, the switching mechanism will reroute the request to a substitute server. This rerouting is transparent to the client.
Initially, this system is not preferred because it necessitates an additional layer of hardware in the network system. Also, this system only conceals errors that occur in the application servers—errors that are "below" the switching mechanism. Therefore, errors that occur in the switching mechanism or "above" the switching mechanism are not addressed by this system and are not transparent to the client. Finally, this system does not address requests that are currently being processed in the application server at the time when the server encounters a fault state.
In all, these conventional systems do not provide a transparent and efficient solution to the problem of temporary or permanent IP and MAC address takeover when a failure occurs in an active computer. The ability to both transparently switch processing from one computer to another, as well as to perform this operation without losing any of the requests or transactions that have been queued but not sent out of the active computer at the time of failure is desired. The present invention preferably addresses at least some of the above problems with the conventional systems.


Both a wireless terminal apparatus and wireless base station apparatus are provided that can, in an operation of encoding the control signals of the upstream link transmitted from the multiple terminal stations while encoding with regard to each of the terminal stations, increase a number of the terminal stations to which different codes are respectively assigned. A wireless terminal apparatus includes: an encoding information receiving portion receiving encoding information which is used at the wireless terminal apparatus from the base station; a phase-shifting unit which conducts a phase-shifting operation on a predetermined first code based on the encoding information; a code selection unit which, based on the received encoding information, selects a second code from multiple codes orthogonally crossing each other; and a control signal encoding portion which conducts an encoding operation on the control signal that is going to be transmitted to the base station by using both the first code on which the phase-shifting operation has been conducted and the second code.

In recent years, a standardization project "3GPP: 3rd Generation Partnership Project" has been discussing a standard regulation of a third generation (3G) mobile communication system. One of topics which has been discussed is a control signal transmission method of an upstream link (link in a direction from a terminal station to a base station).
For example, Non-Patent Document 1 proposes a method of encoding both ACK/NACK signals transmitted from multiple terminal stations and CQI (Channel Quality Indicator) signals at the upstream link with regard to each of the terminal stations. ACK/NACK signals are response signals of 1 bit for confirmation of transmission, ACK signal has a bit "1" used when responding positively, and NACK signal is a bit "0" used when responding negatively. CQI signal is a signal of 5 bits that reports a receiving level.
In a technique of Non-Patent Document 1, ACK/NACK signals and CQI signals are encoded by using "CAZAC (Constant Amplitude Zero Auto Correlation)" code. In this conventional technique, the phase shift amount of CAZAC code used for encoding is varied with regard to each of the terminals. It should be noted that the CAZAC code is a code that has constant amplitude and no autocorrelation.
However, the above-described conventional technique assigns CAZAC code of the different phase shift amount to each of the terminals, but has a problem in which a number of the terminal stations to which the code can be assigned is small.
[Non-Patent Document 1] 3GPP, R1-062742, NTT DoCoMo et al., "CDM-based Multiplexing Method of Multiple ACKJNACK and CQI for E-UTRA Uplink", Oct. 9-13, 2006

This patent is subject to a terminal disclaimer.

Wireless terminal apparatus and wireless base station apparatus


A document taking-over system includes a terminal device provided with an electronic pen which gets information written by hand on a document prepared to be able to specify a kind thereof together with kind information of the document as electronic data and for transmitting the electronic data, a document taking-over apparatus for processing the electronic data to produce it as document information of XML format, a correspondence retrieval apparatus for transmitting connection information to the document taking-over apparatus to the terminal device, and a system disposed at a latter stage to utilize the document information processed by the document taking-over apparatus, which are connected to one another through a network.

The present invention relates to a system for converting handwritten input information into electronic data and a method thereof, and more particularly to a document taking-over system and method for delivering the handwritten input information as the electronic data of a predetermined format to a system that utilizes the data.
Generally, an OCR (Optical Character Recognition) apparatus is used to convert input information handwritten on a document or slip into electronic data in order to process the data in computers or the like. In the OCR apparatus, a scanner is used to read characters handwritten on a document and recognize the read characters to thereby prepare or produce the electronic data. Such an OCR apparatus is defective in that an optical scanner is used to read characters and accordingly a recognition rate of characters is reduced when the layout in the document is complicated.
As a handwritten information input apparatus that solves such a defect, there is an apparatus using an electronic pen. For example, U.S. Pat. No. 6,570,104B1 discloses a handwritten information input apparatus using an electronic pen which can read a special dot pattern which is printed on a document and can specify a position and store the read pattern. The electronic pen of U.S. Pat. No. 6,570,104B1 includes a light emitting diode disposed in a cylindrical body thereof and which irradiates the surface of the document having the special dot pattern printed thereon with light emitted from the light emitting diode and an optical sensor which detects light reflected from the surface of the document to thereby read the dot pattern printed on the surface of the document and store it in a memory of the body. The stored data is analyzed to convert input information handwritten on the document into electronic data. According to the apparatus described in U.S. Pat. No. 6,570,104B1, even if the contents of the document are printed by a complicated layout, only characters written thereon can be converted into electronic data exactly.
However, when it is considered that the apparatus described in U.S. Pat. No. 6,570,104B1 is utilized in cooperation with an existing system such as a business system, the electronic data inputted by the apparatus has no attribute information as to what kind of contents is indicated by individual data contained in the electronic data and accordingly the electronic data cannot be utilized as it is.

System and method for taking over a document


Method and apparatus for activating a slave device are provided. The method including: receiving communication medium scan signals comprising a slave device identifier; controlling a main power supply when the slave device is in an inactive state; determining whether the slave device is completely booted; and executing an upper layer communication when the slave device is completely booted.

1. Field
Apparatuses and methods consistent with the exemplary embodiments relate to activating a device, and in particular, a method and apparatus for activating a device by controlling a power manager by identifying whether a lower layer of a communications protocol is linked.
2. Description of the Related Art
As networks are enhanced and all-internet protocol (all-IP) environments are provided, users utilize desired functions in a convergence environment among various apparatuses including a multimedia terminal (e.g. MP3 players), a personal computer (PC), electronic home appliances, and office apparatuses (e.g. printers).
In a convergence environment, if a user wants to utilize a function of a device (hereinafter referred to as a slave device) by using another device (hereinafter referred to as a master device) that is currently being used by the user, the user may directly turn on the slave device, communication-link the master device to the slave device, and then execute an application of the slave device.
For example, if a user listens to music being played by an MP3 player outside his or her home and upon returning home, wants to listen the music by using a home theater system, the user turns on the home theater system, links the MP3 player to be used by the home theater system to the home theater system, and then executes a music play application of the home theater system.
This process requires multiple user interventions, and the user needs to wait until procedures prior to the execution of the music play application are completely performed in the slave device.

Method and apparatus for activating device


A toner cartridge and a process cartridge, individually, have a shutter which makes sliding movement by opening and closing their toner inlet and toner outlet. When those cartridges are attached to a color printer and fixed together by a fixing lever, the shutters of both cartridges and the fixing lever can move together as one. When they make sliding movement together, both of the shutters are opened and toner supply becomes available. There are thus realized a toner cartridge, a process cartridge, an imaging cartridge, and an image forming apparatus to which those cartridges are attachable, all of which can prevent toner leakage from both a toner housing portion and a process portion and enables even an unaccustomed user to attach each cartridge without making surroundings dirty.

1. Field of the Invention
The present invention relates to an electrophotographic type image forming apparatus and various cartridges which are attached to and detached from the apparatus. More particularly, it relates to a toner cartridge for housing toner, a process cartridge including a process portion, e.g. a developing apparatus or the like, an imaging cartridge including a toner cartridge and a process cartridge therein, and an image forming apparatus to which the above cartridges are attachable.
2. Description of the Related Art
Conventionally, in an electrophotographic type image forming apparatus, a developing apparatus installed therein develops an electrostatic latent image formed on an image carrier with toner and an image is formed thereby. There has occasionally been used an image forming apparatus of which toner housing portion and process portion including a developing apparatus portion are provided as separate units. The toner housing portion and the process portion of such a type image forming apparatus are separately attached to and detached from the main body. Generally, when both of them are attached to a main body of the apparatus and it is in an image-formation-possible state, toner is carried via a toner carrying tube which connects the toner housing portion and the process portion.
When the toner housing portion or the process portion is removed, it is required to prevent toner from dropping out inside the apparatus. Therefore, there has generally been devised a method that a toner carrying tube or the like for connecting units is placed aside or closed. On the other hand, Japanese Unexamined Patent Publication No. 2000-98713 discloses an image forming apparatus of which toner carrying tube is divided at its halfway. According to the Publication, both separated ends of the tube are connected to units, respectively. The tube is connected and disconnected along attachment and detachment of the units. The Publication further discloses an image forming apparatus equipped with a shutter at a connecting portion of a toner carrying tube, wherein the shutter opens and closes along with attachment and detachment of units.
Japanese Unexamined Patent Publication No. 07-152239 discloses an image forming apparatus in which a slide shutter is arranged on a bottom face of a toner cartridge. According to the Publication, a toner cartridge and a toner hopper are engaged with a locking member. Lock with the locking member is unlocked by closing the slide shutter. The mechanism allows a user to detach the toner cartridge when the slide shutter is closed.
However, the above-mentioned conventional image forming apparatuses had the following problems. As to the image forming apparatus directed to the Publication No. 2000-98713, the shutter is opened and closed along attachment and detachment of the units, so the shutter is half-opened in the middle of attachment and detachment operations. Therefore, in the case a user stops attachment or detachment operation in the middle and tries it again from the beginning or in the case a user cannot carry out attachment and detachment operation smoothly, toner can possibly run out from the half-opened shutter.
Furthermore, the image forming apparatus directed to the Publication No. 07-152239 cannot carry out image formation if a user forgets to open the slide shutter after a toner cartridge is attached. Furthermore, since no shutter is provided at its toner hopper side, toner can possibly scatter in the middle of attachment and detachment operation. That is, if a user wishes to keep his/her hands and surrounding clean from toner when attaching and detaching a unit of those conventional apparatus, careful and smooth attachment and detachment operation is demanded. However, proper operation was not easy for a user who rarely carries out the operation.

Toner cartridge, process cartridge, image cartridge, and image forming apparatus to which those cartridges are attachable

Konica Minolta Business Technologies, Inc.


A digital camera is provided with, a voltage detection unit for a driving power supply, a temperature detection unit which detects an inner temperature and an outer temperature of the apparatus, a power supply detection unit which detects whether the power supply is an AC power supply or a DC power supply (battery), a power-supply condition control unit which makes a determination as to a power-supply state of the apparatus based upon a voltage, a temperature and the kind of the power supply that have been respectively detected by the respective detection and monitoring unit; and a focusing unit which automatically focuses a focus lens system onto a subject, and in this arrangement, the gap of automatic focusing timing is varied by an output from the power-supply condition control unit.

In recent years, digital cameras have been developed greatly, and widely used, and various types of them have been supplied to the market. An electronic apparatus such as a digital camera is generally driven by a battery (such as a galvanic cell) from the viewpoint of portable property and mobile property, and in the case of an electronic apparatus driven by a battery, a voltage drop due to the use of the apparatus makes the apparatus operation unstable, therefore, an arrangement has been proposed in which, at the time of a drop of voltage, a voltage-drop display is given (Japanese Patent Application Laid-Open (JP-A) No. 9-130649), or another arrangement has been proposed in which, in the case when a battery has been consumed, a function for allowing the user to see how many more image-pickup operations are available (JP-A No. 2000-253303).
The battery of a digital camera is mainly consumed by displaying images during an image-pickup processor picked-up images on a monitor or flashing process or storing process of images in media such as memories. Moreover, in almost all digital cameras, the focusing operation control is carried out by auto-focusing, and power consumed by motor driving, etc., of the auto-focusing device is not negligible.
Here, in the method disclosed by JP-A No. 2000-253303, in order to consume a battery effectively with high operability while prolonging the battery life, there have been proposed a unit which determines the availability of a reproduction mode for displaying a picked-up image on the monitor or a flashing operation and a unit which inhibits the use of an auto-focusing unit in the case of a drop in voltage.
However, in the above-mentioned conventional art, when the battery voltage drops to a predetermined voltage, the auto-focusing operation suddenly becomes in-operative, causing the user difficulty in handling, and only the battery voltage forms a factor for determining the use of the auto-focusing unit, and no consideration is given to a case in which, in a cold place, the battery voltage suddenly drops due to degradation in the battery performance or a case in which an AC adapter that is not susceptible to a drop of power-supply voltage. Furthermore, the user is not allowed to switch the automatic focusing operation, and no consideration is given to a case when the user desires to increase the processing speed rather than saving the battery.

Automatic focus control based on voltage, temperature, and power supply


This disclosure relates to a method for making a polymeric article mold, a method for making a polymeric article with that mold, and improved surface topography features for a polymeric article. A prototype article is formed and then coated with a thin conductive layer. The coated prototype article is then electroformed until nickel plated to a sufficient depth to define a nickel plating tool. After the prototype article has been removed from the mold face of the nickel tool, the tool can be used as a mold for forming finished polymeric articles which replicate the original prototype article. The use of fine topography features such as a dense upstanding stem array on the surface of the prototype article facilitates accurate and complete electroforming by increased surface area presentation. The disclosure also presents improvements to microreplicated surface structures such as stem arrays. The improvements include the formation on a stem array having separate zones of stems of differing heights, and the formation of directional microreplicated features (e.g., stems) which are oriented and shaped to promote or restrict frictional interaction in one or more particular directions.

The present invention is directed to improvements in forming molded polymeric articles, and includes a method for making microreplicated articles and a method of making molds for such articles for use in injection or insert molding processes. The present invention also is directed to improved surface topography features for polymeric articles.
Minnesota Mining and Manufacturing Company has recently introduced a friction control material for use on glove and handle wrap applications which facilitates high slip resistance in the direction of shear, in wet or dry conditions. This material, known as GREPTILE™ gripping material is commercially available in sheet and strip form. The material has a surface defined by an array of elastomeric uniformly shaped upstanding stems which are highly flexible. When a normal force is applied to the stem array surface, the stems deform and bend over, thereby increasing the effective surface area of the gripping material relative to the applied shear forces. The material thus presents an aggressive friction control surface. When used with a like material in an opposed relation, the stems of the two materials interengage, thereby presenting even more surface area to each other for relative frictional interface. The stems do not interlock, however, so virtually zero peel force is required to separate the two opposed stem arrays. This material is more fully disclosed in U.S. Pat. No. 6,610,382 (which is incorporated by reference herein), commonly owned by the applicant herein, 3M Innovative Properties Company.
Known stem-web containing polymeric articles are often formed by molding techniques. When the desired article includes intricate or numerous topography features, the mold must necessarily include such intricate and numerous topography features, in mirror image. Creating such intricate features on molds has heretofore been a relatively expensive proposition. For instance, if the mold is to include microreplicated features such as generally cylindrical headless stem elements, the mold must include a hole or channel for each stem to form therein, and those holes must thus be individually drilled in the mold material. Attempts to use mold segment replication have been tried, but such an approach is limited by molding and pattern materials that will suffice for such replication purposes for a microreplicated surface, and still result in relatively expensive mold production techniques.


The present invention relates to light-emitting diodes. A light-emitting diode according to an exemplary embodiment of the present invention includes a first group including a plurality of first light emitting cells connected in parallel to each other, and a second group including a plurality of second light emitting cells connected in parallel to each other. Each first light emitting cell and second light emitting cell has a semiconductor stack that includes a first conductivity-type semiconductor layer, a second conductivity-type semiconductor layer, and an active layer disposed between the first conductivity-type semiconductor layer and the second conductivity-type semiconductor layer. At least two light emitting cells of the first light emitting cells share the first conductivity-type semiconductor layer, and at least two light emitting cells of the second light emitting cells share the first conductivity-type semiconductor layer. The first light emitting cells are connected in series to the second light emitting cells.

1. Field of the Invention
Exemplary embodiments of the present invention relate to light-emitting diodes and to light-emitting diodes having electrode pads, and more particularly, to high voltage and/or high efficiency light-emitting diodes.
2. Discussion of the Background
Gallium nitride (GaN) based light emitting diodes (LEDs) have been used in a wide range of applications including full color LED displays, LED traffic signals, and white LEDs.
The GaN-based light emitting diode may be generally formed by growing epitaxial layers on a substrate, for example, a sapphire substrate, and includes an N-type semiconductor layer, a P-type semiconductor layer, and an active layer disposed between the N-type semiconductor layer and the P-type semiconductor layer. Further, an N electrode pad is formed on the N-type semiconductor layer and a P electrode pad is formed on the P-type semiconductor layer. The light emitting diode is electrically connected to and operated by an external power source through these electrode pads. Here, electric current is directed from the P-electrode pad to the N-electrode pad through the semiconductor layers.
Generally, since the P-type semiconductor layer may have a high resistivity, electric current may not be evenly distributed within the P-type semiconductor layer, but may be concentrated on a portion of the P-type semiconductor layer where the P-electrode pad is formed. Electric current may be concentrated on and flow through edges of the semiconductor layers. This may be referred to as current crowding, and may lead to a reduction in light emitting area, thereby deteriorating luminous efficacy of a source. A transparent electrode layer having a low resistivity may be formed on the P-type semiconductor layer to enhance current spreading. In this structure, electric current supplied from the P-electrode pad may be dispersed by the transparent electrode layer before entering the P-type semiconductor layer, thereby increasing a light emitting area of the LED.
However, since the transparent electrode layer may tend to absorb light, the is thickness of the transparent electrode layer is limited, thereby providing limited current spreading. In particular, for a large LED having an area of about 1 mm2 or more, there is a limitation on current spreading through the transparent electrode layer.
To facilitate current spreading within a LED, extensions extending from the electrode pads may be used. For example, U.S. Pat. No. 6,650,018, issued to Zhao, et al. discloses an LED that includes a plurality of extensions extending in opposite directions from electrode pads to enhance current spreading. Although the use of extensions may enhance current spreading over a wide region of the LED, current crowding may still occur at portions of the LEDs where the electrode pads are formed.
Moreover, as the size of the LED increases, the likelihood of a defect being present in the light emitting diode may increase. Defects such as threading dislocations, pin-holes, etc. provide a path through which electric current may flow rapidly, thereby disturbing uniform current spreading in the LED.
A light emitting device having a plurality of light emitting cells serially connected to each other in a single chip to operate under high voltage is disclosed in U.S. Pat. No. 7,417,259, issued to Sakai, et al.
Recently, light emitting devices capable of being powered by 110 V or 220 V domestic alternating current (AC) power sources have been commercialized. In such a light emitting device, chips each having a plurality of light emitting cells serially connected to each other are mounted in a package to be serially connected to each other, and each package may be used together with a bridge rectifier. Two to four light emitting diode chips, each of which includes sixteen to twenty light emitting cells serially connected to each other on a single substrate, may be connected in series within a package to be powered by 110 V or 220 V power sources.
Particularly, assuming that each light emitting cell is powered by a forward voltage of about 3.5V, three to fifteen light emitting cells are serially connected to each other in order to provide high voltage products, such as 12V, 24V, 36V, 48V, and the like, to which a switching mode power supply (SMPS) is applied. Since a power of about 3 to 11 W may be applied to high voltage products, relatively high electric current may be supplied to each of the light emitting cells. In this case, if the light emitting cells have excessively small sizes, current density may be excessively increased, thereby deteriorating reliability. On the contrary, if the light emitting cells have excessively large sizes, electric current may not be uniformly distributed, thereby causing current crowding and deteriorating light extraction efficiency.
FIG. 7 is a schematic plan view explaining a conventional high voltage light emitting diode and FIG. 8 is a schematic circuit diagram of FIG. 7. Here, three light emitting cells are connected in series.
Referring to FIG. 7 and FIG. 8, a conventional light emitting diode includes a substrate 21, light emitting cells C1, C2, C3, a cathode 37, an anode 39, interconnecting sections 41, first electrode pads 35, and second electrode pads 33.
The light emitting cells C1, C2, C3 are separated from each other on the substrate 21 and each includes a first conductive type semiconductor layer 23, an active layer (not shown), and a second conductive type semiconductor layer 27. Here, the first conductive type semiconductor layer 23 is an n-type semiconductor layer, and the second conductive type semiconductor layer 27 is a p-type semiconductor layer. In the light emitting cells C1, C2, C3, the first conductive type semiconductor layers 27 are separated from each other, so that each of the light emitting cells C1, C2, C3 constitutes each unit U1, U2, U3. A transparent electrode layer (not shown) may be placed on the second conductive type semiconductor layer 27.
The cathode 37 is placed on the first conductive type semiconductor layer 23 of each of the light emitting cells Cl, C2, C3, and the anode 39 is also placed on the second conductive type semiconductor layer 27 of each of the light emitting cells Cl, C2, C3. The cathodes 37 and the anodes 39 may be distributed in alternate arrangement over a wide area for current spreading.
Meanwhile, in adjacent light emitting cells, the cathode 37 is serially connected to the anode 39 via the interconnecting section 41. Accordingly, as shown in FIG. 8, it is possible to provide a light emitting diode having three serially connected light emitting cells and powered by, for example, a 12V power source.
In this light emitting diode, two first electrode pads 35 and two second electrode pads 33 are provided for current spreading, and the anode 39 and cathode 37 extend on each of the light emitting cells C1, C2, C3.
However, since the anode 39 and the cathode 37 are formed to relatively large sizes in order to obtain uniform current spreading on a large scale chip having, for example, a size of 1 mm×1 mm or more, optical loss inevitably occurs due to the anode and cathode 37, 39. Furthermore, since a relatively long anode 39 is placed on a single light emitting cell, current crowding is likely to occur near the second electrode pads 33. Moreover, since each light emitting cell has a relatively large light emitting area, light extraction efficiency is further deteriorated due to low current density.
On the other hand, for a light emitting diode in which a relatively large number of light emitting cells, for example, 15 light emitting cells, are serially connected in each of chips having the same size, the light emitting cells have small sizes so that current density increases in the light emitting cells, thereby deteriorating reliability.

Light emitting diode having electrode pads


The improved folding door and door frame assembly includes a door frame having a horizontal top channel member adapted to receive a number of depending door slides, and a vertical side frame member below the channel member. The assembly also includes a folding door formed of an array of interconnected, parallel, vertically extending polyvinyl chloride slats arranged in side by side relation. The slats have small staple fibers substantially uniformly distributed throughout the body thereof to give the slats a translucent sandy appearance and feel. Each slat in the arry preferably is corrugated to provide a number of integral parallel segments. Each slat has an integral side folding hinge extending along the length of one side thereof and a hinge-receiving slot or groove along the length of the opposite side of the slat. The slats are interconnected through the side hinges and grooves. The slat on one side of the array is connected to the door side frame through its side hinge, while the slat on the opposite side of the array is connected to a handle-bearing side panel through the side hinge of the panel. Preferably, the panel and frame are textured to match the slats. The aforementioned slides are connected to the upper ends of the side panel and slats to hold them in the vertical position in the frame.

1. Field of the Invention
The present invention generally relates to a polyvinyl chloride (PVC) folding door and door frame assembly and to an improved method of making the same.
2. Prior Art
Various types of folding doors are currently available. Some are of vertical wood slats hinged together and hung by slides from a door frame. Others are fabricated of smooth surfaced opaque PVC panels, which provide, when closed across a doorway, a sterile, cold, flat, blank appearance which is generally unattractive.
Accordingly, it would be desirable to be able to provide an improved PVC folding door which transmits some light, even when closed, is inexpensive and attractive in appearance and which does not look smooth, plastic, hard and cold. Preferably, the door should be easy to assemble and have a novel textured natural appearance which is permanent and which more closely blends in with other decorative features.

Textured folding door and frame assembly


In a composite molded lens, a press-formed lens body is integral with an injection-molded lens frame. The lens body has a lens portion and a flange portion surrounding the lens portion. Eight projections are radially formed on a top surface of the flange portion. The height of the projection increases toward an outer peripheral edge side of the flange portion. A recess is formed on an outer peripheral edge face of the flange portion and located at a position on a line extending from the projection. The recess increases torsional resilience of a joint surface between the lens body and the lens frame and strengthens bonding force there between.

1. Field of the Invention
The present invention relates to a composite molded lens formed by press-forming and injection molding and a method for producing a composite molded lens.
2. Description Related to the Prior Art
A digital camera, a mobile terminal with a camera, or the like uses a taking lens to form an image of a subject on an image sensor. A projector uses a projector lens to project an image, which is displayed on a liquid crystal display, onto a screen. A molded lens is generally used as an optical lens such as the taking lens or the projector lens. The molded lens is produced by press-forming a preform (lens material) while the preform is heated.
The molded lens has advantages that it has high optical performance and eliminates the need for after-treatment such as grinding. However, it is difficult to form a positioning or alignment face, which is perpendicular to the optical axis, and an outer peripheral end face, which is fitted into a lens frame, of the molded lens. Hence, it is difficult to align the position of the molded lens in the lens frame or a lens barrel or to improve the accuracy of centering the molded lens. Recently, small molded lenses and large-diameter molded lenses have been developed and there has been a tendency to reduce the lens thickness relative to outer-diameter dimensions. In a case where the thickness of the molded lens, particularly, a convex lens, is further reduced, an outer peripheral portion thereof becomes extremely thin. This makes it difficult to attach the lens frame to the molded lens. As a result, the accuracy of attaching the lens frame or the like to the molded lens is further reduced.
For this reason, it is suggested to integrally form the lens frame around the outer periphery of the lens. For example, in Japanese Examined Patent Publication No. 07-98669, first and second molds are used to apply pressure to a lens material (preform) while the lens material is heated, and thereby an optical element (lens body) is produced. During the application of the pressure, an outer peripheral portion of the optical element is squeezed out of inner side portions of the first and second molds and projects into a cavity between the first and second molds. Molten resin is filled in the cavity to form an optical element frame (lens frame) by injection molding. Thereby the optical element frame is bonded to the outer peripheral portion of the optical element, and thus an optical element (composite molded lens) is formed integrally with the optical element frame.
Japanese Patent Laid-Open Publication No. 2007-22905 also discloses producing an optical element device (composite molded lens) by use of first and second molds. Glass is press-formed with the first and second molds while being heated, and thereby an optical lens (lens body) is produced. Then resin is injection-molded to form a frame (lens frame) integrally with the optical lens. Thus, the optical element device (composite molded lens) is produced. In this optical element device, a flat portion (flange portion) is formed around the outer periphery of the optical lens to prevent the resin from flowing onto the surface of the optical lens during the injection molding of the frame. The frame is tightly bonded to the outer peripheral end face of the flat portion.
In a case where the lens frame is injection-molded around the outer periphery of the press-formed lens body, the problem arises that the bonding performance (tight bonding performance) of a joint surface or interface between the outer periphery of the lens body and the lens frame is insufficient. The insufficient bonding performance may result in separation of the lens frame from the lens body due to difference in expansion, which is caused by a change in environment temperature, or a curve or twist at the time of attaching the optical element device to a lens barrel.

Composite molded lens and method for producing the same


A film-formation method for a semiconductor process includes seed film formation and main film formation. In the seed film formation, a metal-containing raw material gas and a first assist gas to react therewith are supplied into a process container, which accommodates a target substrate having an underlying layer, thereby forming a seed film on the underlying layer by CVD. In the main film formation, the raw material gas and a second assist gas to react therewith are supplied into the process container, thereby forming a main film on the seed film by CVD. The seed film formation includes first and second periods performed alternately and continuously. In each first period, the raw material gas is supplied into the process container while the first assist gas is stopped. In each second period, the first assist gas is supplied into the process container while the raw material gas is stopped.

1. Field of the Invention
The present invention relates to a film formation method and apparatus for a semiconductor process, which are used for forming a thin film on a target substrate, such as a semiconductor wafer. The term "semiconductor process" used herein includes various kinds of processes which are performed to manufacture a semiconductor device or a structure having wiring layers, electrodes, and the like to be connected to a semiconductor device, on a target substrate, such as a semiconductor wafer or a glass substrate used for an LCD (Liquid Crystal Display) or FPD (Flat Panel Display), by forming semiconductor layers, insulating layers, and conductive layers in predetermined patterns on the target substrate.
2. Description of the Related Art
In manufacturing semiconductor devices for constituting semiconductor integrated circuits, a target substrate, such as a semiconductor wafer, is subjected to various processes, such as film formation, oxidation, diffusion, reformation, annealing and etching, in general. For example, where a wiring structure is formed, a target substrate is provided with a film of a metal or metal compound thereon, such as W (tungsten), WSi (tungsten silicide), Ti (titanium), TiN (titanium nitride), TiSi (titanium silicide), Cu (copper), Ta2O5 (tantalum oxide).
In recent years, semiconductor devices have become smaller and more highly integrated, thereby making the design rule on the size of each semiconductor device stricter, i.e., miniaturized. Under the circumstances, capacitors formed of semiconductor devices are therefore required to be further smaller. In this respect, for example, it has been proposed to use a three dimensional device structure, because a larger capacitance can be obtained with the same occupied surface area. Further, in order to increase capacitance, a thin film of a dielectric oxide (a material wit a high dielectric constant), a representative of which is BST (barium strontium titanium oxide), is used as a capacitor insulating film.
It has been studied to use an Ru film (ruthenium film) or RuO2 film (ruthenium oxide film) as a capacitor electrode, so as to reduce the resistance, along with such a capacitor insulating film with a high dielectric constant. Jpn. Pat. Appln. KOKAI Publication Nos. 11-354751, 2001-345285, and 2003-68676 disclose techniques concerning capacitor electrodes of this kind.
FIGS. 7A and 7B are sectional views showing sequential steps of a conventional method for forming an Ru film. Since raw material gases of an Ru film have low surface adsorptivity, it is difficult to directly deposit an Ru film on an underlying layer by CVD (Chemical Vapor Deposition). Accordingly, as shown in FIG. 7A, a seed film 2 of a very thin Ru film is first formed on the underlying layer of a semiconductor wafer W by a sputtering process performed in a sputtering apparatus, which utilizes plasma.
Then, the semiconductor wafer W with the seed film 2 formed thereon is unloaded from the sputtering apparatus and loaded into a CVD apparatus. Then, as shown in FIG. 7B, a CVD process is performed at a high film-formation rate to form a main film 4 of an Ru film over the entire surface of the wafer W including the inner wall of a recess 6. In the CVD process, since the seed film 2 is present below, the Ru film is easily deposited, using the seed film 2 as nuclei. As a consequence, the film is formed on the inner wall of a recess 6 with high step coverage (degree of covering a step portion). This CVD process employs a raw material gases, such as biscyclopentadienyl ruthenium (which may be referred to as Ru(C5H5)2 or Ru(Cp)2), and oxygen gas.

Film formation method and apparatus for semiconductor process


A separated overfire air injection system particularly suited for use in a fossil fuel-fired steam generating power plant and more specifically to a sixpoint separated overfire air tangential firing system employed in such power plants, particularly those embodying dual-chambered furnaces. A method of operating such a fossil fuel-fired steam generating power plant equipped with the sixpoint separated overfire air injection system of the present invention is also disclosed. The separated overfire injection system in accordance with the present invention includes six SOFA windboxes strategically located about the perimeter of the dual-chambered furnace volume so as to be operative to inject separated overfire air into the furnace volume in such a manner as to engage a fireball symmetrically tangential to a circle. Furthermore, the separated overfire air injection system, when so employed, produces a mixing index that is substantially equivalent over the elevations in the furnace in which mixing of separated overfire with generated flue gases occurs, which is achieved through the use of four SOFA windboxes as done heretofore in the prior art or as in accordance with the teachings of the present invention with three SOFA windboxes per each chamber of the furnace volume.

This invention relates to the use of tangential firing systems in fuel-fired steam generating power plants and more specifically to a sixpoint separated overfire air tangential firing system employed in power plants which utilize dual-chambered furnaces.
In general the tangential firing technique involves the introduction of combustible fuel and air into a furnace volume from multiple locations about the perimeter of the furnace volume in such a manner that the fuel and air are directed tangent to an imaginary circle which lies in a horizontal plane and is concentric with the furnace volume. The fireball that results from the combustion of the fuel and air thus rotates about the center of the imaginary circle. This type of firing has many advantages, among them being good mixing of the fuel and air, stable flame conditions and long residence time of the combustion gases in the furnace.
In recent years, due to very strict state and federal environmental regulations demanding that emissions be maintained at acceptable levels, greater emphasis has been placed upon minimizing air pollution generated from these power plants. To this extent, oxides of nitrogen, also known as NO.sub.X, have beet implicated as one of the constituents that contribute to the generation of acid rain and smog.
Oxides of nitrogen are a byproduct of the combustion of hydrocarbon fuels, such as pulverized coal in air, and are found in two main forms. If the nitrogen originates from the air in which the combustion process occurs, the NO.sub.X is referred to as `thermal NO.sub.X.` Thermal NO.sub.X forms when very stable molecular nitrogen, N.sub.2, is subjected to temperatures above about 2800.degree. F. causing it to break down into elemental nitrogen, N, which can then combine with elemental or molecular oxygen to form NO or NO.sub.2. The rate of formation of thermal NO.sub.X downstream of the flame front is extremely sensitive to local flame temperature and somewhat less so to the local mole concentration of oxygen. Thermal NO.sub.X concentration can be reduced by lowering the mole concentrations of N.sub.2 and O.sub.2, reducing the peak flame temperature and reducing the amount of time that N.sub.2 is subjected to these temperatures.
If the nitrogen originates as organically bound nitrogen within the fuel, the NO.sub.X is referred to as `fuel NO.sub.X.` The nitrogen content of coal, for instance, is comparatively small and, although only a fraction is ultimately converted to NO.sub.X, is the primary source of the total NO.sub.X emissions from a steam generating power plant. The formation rate of fuel NO.sub.X is strongly affected by the rate of mixing between the fuel and air stream in general, and by the local oxygen concentration in particular. The formation of fuel NO.sub.X is a multi-stage process. During initial coal particle heat up the coal is broken down into both volatile matter consisting of reactive cyanogens, oxycyanogens and amine species and char consisting of unburned carbon, hydrocarbons and ash. In an oxygen rich environment the volatile matter will convert largely to NO.sub.X and in a fuel-rich environment it can be reduced to N.sub.2. The remaining fuel-bound nitrogen is released during combustion of the carbon based byproducts, i.e. char, of the combustion of the coal particles. For char combustion to approach completion, an oxygen rich process is required. As with the volatile released NO.sub.X, the eventual fate of char released nitrogen is dependent upon the specific time, temperature and stoichiometric history.
The stoichiometric ratio, .phi., of a combustion process is defined here as the number of moles of oxygen supplied to combust a given quantity of fuel divided by the number of moles of oxygen theoretically necessary to combust the same quantity of fuel. Typically, the stoichiometric ratio in a fossil fuel-fired steam generating power plant is a quantity greater than or equal to one and can be expressed as a percentage in which case it is referred to as percent theoretical air, .tau.=.phi..times.100. A related term is excess air which is (.phi.-1).times.100 or .tau.-100.
From the preceding it should be apparent that by controlling the distribution and mass flow rate of air to the combustion process the stoichiometric ratio of the process can be controlled and thus also the formation of NO.sub.X. One method of controlling the distribution and mass flow rate of air to the combustion process occurring within a tangentially fired furnace is through the use of staged combustion. In accordance with staged combustion typically there is defined a main burner zone within the furnace volume. Within the main burner zone fuel, is initially only partially combusted in a fuel-rich environment by withholding a portion of the total air necessary for complete combustion. Next that portion of air which has been withheld from the main burner zone, and which is sometimes referred to as overfire air (OFA), is introduced into the furnace volume above the main burner zone, frequently at multiple elevations. A typical configuration of overfire air is found in the utilization of one or two closely grouped compartments at a single, fixed elevation near the top of a plurality of vertically arrayed compartments housed within a common vertical plenum known as a windbox. This overfire air is generally referred to as close coupled overfire air (CCOFA). In addition, at a higher elevation, and separated from the main windbox, separated overfire air (SOFA) is introduced into the furnace volume from a similar group of compartments located in a SOFA windbox. The use of separated overfire air in a tangentially fired furnace can be seen, by way of exemplification and not limitation, in U.S. Pat. Nos. 5,020,454, 5,195,450, 5,315,939 and 5,343,820, each of which teaches the use of a plurality of separated overfire air compartments.
Upon introduction into the furnace volume above the main burner zone the separated overfire air is mixed with and finally combusted with the products generated by the incomplete combustion occurring within the main burner zone. The use of close coupled and separated overfire air minimizes NO.sub.X formations via two mechanisms. First, by having a fuel-rich atmosphere in the main burner zone, i.e., a so called substoichiometric condition, the initial amount of fuel NO.sub.X formed is reduced because less oxygen is available to combine with the fuel-bound nitrogen. Second, lower fuel NO.sub.X results because of the reduced air concentrations during the initial firing stage. Thus, this has the effect of increasing the residence time within the main burner zone. To this end, residence time is the amount of time necessary for a fuel particle to combust. The increased residence time provides an environment, which is conducive to the reduction of any oxidizable N.sub.2 volatiles that have been formed such as NH.sub.3 or HCN. This is because the NO.sub.X compounds and the volatiles are entrained and reduced to their elemental components, oxygen and nitrogen, and because the hydrocarbons are combusted. Furthermore, the use of overfire air has the effect of reducing the peak flame temperatures, thereby resulting in lower thermal NO.sub.X formation.
In accordance with a typical configuration of a tangentially fired furnace wherein both staged combustion and overfire air are being utilized, fuel plus primary air, as well as secondary air and close coupled overfire air, are supplied, by means of a forced draft fan and various ducts, to a main windbox. From the main windbox, in accordance with conventional practice, the fuel and air are then introduced into the furnace volume. Primary air is used to transport solid fuel to the windbox and secondary air and close coupled overfire air are used to control the stoichiometric ratio within the main burner zone. The flow rates of secondary air and close coupled overfire air are controlled by individual dampers located within the main windbox. Furthermore, in accordance with a typical configuration of a tangentially fired furnace, main windboxes may be located at or near the corners of the furnace volume with fuel and air directed tangential to an imaginary circle, which lies in a horizontal plane and is concentric with the furnace volume. However, tangential firing may also be accomplished with windboxes located at or near the mid-wall of the furnace sides. U.S. Pat. No. 5,429,060 discloses the use of burners disposed at the central portions of respective sides in a horizontal cross-section of a furnace wall and U.S. Pat. No. 5,315,939 discloses an integrated low NO.sub.X tangential firing system.
In many existing power plants a dual-chambered furnace volume is provided wherein the combustion process takes place. Typically tangential firing is accomplished in these power plants via four main windboxes per chamber suitably located at appropriate points along the front and rear waterwalls, which along with the side waterwalls serve to define the furnace volume. However, such furnaces may not be equipped with close coupled overfire air and/or separated overfire air. Instead, the main windboxes and associated ductwork may simply direct fuel along with primary air and secondary air into the respective chambers. In a dual-chambered furnace volume, the resulting combustion of the fuel and air injected thereto yields two rotating fireballs. Each of these two rotating fireballs is coaxial with the center of a corresponding one of the dual chambers of the furnace volume.
It should be readily apparent from the foregoing that in a tangentially fired furnace, it is desirable to reduce the formation of NO.sub.X during the combustion process itself. This is in fact a matter of critical importance and a major concern in the design and operation of new power plants as well as in the retrofitting of existing plants. Reducing the formation of NO.sub.X during the combustion process obviates the need for expensive post combustion air pollution devices. However, without overfire air and the attendant NO.sub.X reducing capabilities that it affords, it is difficult for power plants not so equipped to meet state and federal NO.sub.X emission requirements. Therefore, in order to meet these requirements, it is desirable to equip the furnaces of these power plants with separated overfire air (SOFA).
In a retrofit application there are, however, numerous difficulties that need to be overcome, before the furnaces of these power plants can, without sacrificing the aforementioned advantages of tangential firing (good mixing of fuel and air, stable flame conditions and long residence time of combustion gases in the furnace), be equipped with separated overfire air. First, it is necessary to maintain the total mass flow rate of air, which is to be introduced into the respective chambers of the multi-chambered furnace volume. This means that the totality of primary air, secondary air, and close coupled overfire air if present, before retrofit, is equal to the totality of primary air, secondary air, close coupled overfire air and the retrofitted separated overfire air. Furthermore, the totality of the mass flow rate of fuel introduced into the furnace volume must remain the same before and after the retrofitting of the separated overfire air. Maintaining the totality of the mass flow rates of air and fuel furthermore must be accomplished while the total mass flow rate of output steam produced by the power plant is also being maintained. In addition, it is also necessary that the management of the fireball remains consistent before and after the retrofitting. By the management of the fireball is meant the ability to maintain the stability of the fireball as well as its shape and location within the respective chambers of the multi-chambered furnace volume. Still further it is necessary to minimize the number of expensive penetrations that are required to be made through the waterwalls of the furnace volume in order to retrofit the separated overfire air. Moreover, it is desirable to do so because of the limited space that is available to accommodate added ductwork. In view of the need to minimize the number of waterwall penetrations, it is also desirable to accomplish the retrofitting of the separated overfire air with a minimum number of SOFA windboxes.
The present invention is capable of addressing these needs while maintaining the low NO.sub.X advantages of tangentially fired staged combustion. This is achieved by providing six SOFA windboxes strategically located about the perimeter of each chamber of a dual-chambered furnace volume at an elevation above the main burner zone and oriented so as to inject separated overfire air into each chamber in such a manner that the mixing of the separated overfire air with the flue gases generated therein is substantially equivalent whether three SOFA windboxes are used or four SOFA windboxes are used.
As alluded to above, it is essential for purposes of achieving efficient combustion that there be as thorough and complete a mixing of fuel and air as possible. To that end, it has been found that, in accordance with the present invention, separated overfire air delivered to the respective chambers of a dual-chambered furnace volume by means of three strategically spaced SOFA windboxes per chamber results in a mixing of separated overfire air and the combustion gases in the furnace volume that is virtually identical to the mixing which is achieved through the utilization of more than three SOFA windboxes per chamber, e.g., four SOFA windboxes per chamber. Furthermore, in the present invention, flame stability, shape and location within the chamber are not degraded when three SOFA windboxes are used as opposed to the use of more than three SOFA windboxes, e.g., four SOFA windboxes. Also in the present invention, a furnace volume retrofitted with three SOFA windboxes will still enable that there be the long residence time of the combustion gases in the furnace volume which is inherent with the employment of the overfire air concept to be realized. Also in accordance with the present invention it is still possible to maintain the totality of the mass flow rates of fuel and air delivered to the furnace volume while yet maintaining the totality of the mass flow rate of output steam of the power plant when the subject matter of the present invention is employed in a retrofit application. Furthermore, in accordance with the present invention a minimum number of expensive waterwall penetrations and attendant ductwork associated with SOFA windboxes are required. Still further, the subject matter of the present invention, although primarily intended for application in dual-chambered furnace volumes, is equally applicable to both dual-chambered and single-chambered furnace volumes.
It is, therefore, an object of the present invention to provide a new and improved separated overfire air system which is particularly suited for use in a dual-chambered furnace volume.
It is also an object of the present invention to provide such a new and improved separated overfire air system for use in a dual-chambered furnace volume, which is characterized in that through the use thereof the mass flow rate of fuel and the mass flow rate of air delivered to the respective chambers of the dual-chambered furnace volume remains unchanged after being retrofitted therein.
It is a further object of the present invention to provide such a new and improved separated overfire air system for use in a dual-chambered furnace volume, which is characterized in that through the use thereof the mass flow rate of output steam remains unchanged after being retrofitted therein.
It is still a further object of the present invention to provide such a new and improved separated overfire air system for use in a dual-chambered furnace volume, which is characterized in that through the use thereof the ability to maintain fireball stability, shape and position within the respective chambers of the dual-chambered furnace volume is unaffected when retrofitted therein.
It is yet a further object of the present invention to provide such a new and improved separated overfire air system for use in a dual-chambered furnace volume which is characterized in that the use thereof necessitates only a minimum number of waterwall penetrations and attendant ductwork for purposes of effecting the retrofit thereof therein.
It is also an object of the present invention to provide such a new and improved separated overfire air system for use in a dual-chambered furnace volume, which is characterized in that through the use thereof it is possible therewith to effect a reduction in the formation of NO.sub.X in the combustion process occurring within the respective chambers of the dual-chambered furnace volume.
It is still further an object of the present invention to provide such a new and improved separated overfire air system for use in a dual-chambered furnace volume which is characterized in that through the use thereof it is possible to achieve mixing of separated overfire air with combustion gases in the furnace volume which is very nearly equivalent from the use of three SOFA windboxes to that attainable with more than three SOFA windboxes, e.g., four SOFA windboxes.
It is another object of the present invention to provide such a new and improved separated overfire air system for use in a dual-chambered furnace volume which is characterized in that it is equally well suited for use either in retrofit applications or in new applications.
It is yet another object of the present invention to provide such a new and improved separated overfire air system, which is characterized in that it is employable in both dual-chambered as well as single-chambered furnace volumes.
It is still further an object of the present invention to provide such a new and improved separated overfire air system for use in a dual-chambered furnace volume, which is characterized in that it is relatively easy to install, relatively simple to operate, yet is relatively inexpensive to provide.

Separated overfire air injection for dual-chambered furnaces