Abstract: Disclosed is a circuit to amplify a signal generated by the varying conductance of a photoconductor and to bias the photoconductance for optimum performance. A transistor means, with base input being proportional to the photoconductor's conductance and output being 180.degree. out of phase with the input is coupled to an operational amplifier where said output is further amplified. Part of this inverted amplified output is then used to bias the photoconductor, immediately offsetting a changed voltage across the photoconductor and keeping voltage across the photoconductor constant.

Abstract: In a computer device, an instruction set which uses a two-instruction sequence to store the result of a comparison is provided. The two-instruction sequence, which uses no branch instructions, does not need to wait for condition resolution before storing conditional results. Additionally, it also is capable of implementing slightly more general operations than simply storing a zero or one value of a comparison. Basically, the instruction set in accordance with the invention compares two operands and unconditionally stores a zero, which represents a Boolean "false", into a selected destination. The instruction set then conditionally nullifies the instruction following it, thus effecting a highly efficient execution of a sequence of instructions compared to the prior art.

Abstract: A basic instruction for moving a string of bytes in a word has been devised. Because the operations in the instruction are basic, very few variations are necessary to accommodate diversity of lengths and variables. These operations are imbedded in a single code sequence; the compiler can therefore generate exactly the minimum sequence necessary to perform the operations and can precompute many of the operands at compile time, typically completing the instruction within a single cycle time. The control necessary to optimize the operations is then in the compiler instead of the hardware.

Abstract: A structure and method for use in optical communication systems is provided in which a metal is diffused in a heterojunction region beneath a metal contact of a AlGaAs light emitting diode. This structure and method significantly reduces the contact shadowing problem due to current crowding beneath the contact thus increasing the light output from the device.

Abstract: A plurality of different liquid solutions are connected to an input of a pump system having at least two displacement chambers and in a manner to control the proportions of each constituent that are taken into each chamber during its intake stroke. The outputs of the chambers are connected to a common liquid output. The chambers are driven by independently controllable motors so that the discharge stroke may be chosen to have some parameters, such as speed profile and duration, that are different than during the intake stroke. As a result, both chambers may simultaneously discharge liquid through the common output, if desired. The proportion of constituents may be made different each time one of the chambers is filled, so the simultaneous discharge of the chambers allows a gradual, carefully controlled change from the mixture of one chamber to that of the other.

Abstract: An interferometer in which an input beam is divided into two beams, the first of which is incident on a movable first reflecting surface before being recombined in an output beam with the second of the beams. The path for each beam is selected to be as similar as possible to the path for the other beam so that small rotations or translations of elements used to direct the beams affect both equally and so that changes in the ambient conditions affect both beams equally. The two beams are directed by reflecting elements, each of which reflects both beams an equal number of times so that small rotations of the elements affect both beams equally. The second beam is incident on a second reflecting surface near the first surface so that the deadpath between the first and second surfaces is as small as possible without interfering with the motion of the first surface.

Abstract: This invention supports a moving mirror in an interferometer, so that movement is restricted to a linear movement perpendicular to the plane of the mirror, and provides a means to impart a motion to the mirror. Two flat springs are connected at their centers with a beam. A mirror is affixed flush against the center portion of one of the springs, and a frame holds the edges of the springs fixed so that the beam and mirror can only move perpendicular to the plane of the springs and mirror. A voice coil is attached to the center of the other spring to impart motion to the beam and mirror.

Abstract: A method and an apparatus for communications systems provide priority to packets entering a communications node from a network to enable transmission of these packets in an orderly and efficient fashion. By defining a through-traffic preemptive priority mode, local packets are held in abeyance until packets which are already on the network and detected at the communications node have been routed through the node. Then the local packets are allowed to be transmitted from the node. And by defining a through-traffic priority mode, the local packet once started is completely transmitted before the network packets entering the communications node are allowed to continue through the system.

Abstract: An automatic lead sensing and fine-forming system is disclosed for preparing the leads of electronic compnents so that they are ready to be inserted by robots into holes on printed circuit boards. The positions of the lead tips and the positions of the holes are sensed and compared to determine if any leads need to be bent. These leads are then bent and the force on the leads and their displacement are sensed and recorded during the process. The data recorded is then used for subsequent bendings, where necessary, for bending the leads to the target locations so that all the leads fit simultaneously into the holes. To simplify image processing, the lead tips are illuminated by light originating from substantially isotropic directions from locations substantially coplanar with the region of the lead tips.

Abstract: In the fabrication of integrated circuits, a polymethyl methacrylate film containing a selected dye and exhibiting a strong dependence on light intensity is photobleached to provide an optical mask to pattern an underlying photoresist layer. While the film is photobleached, the underlying photoresist layer is made to be substantially unaffected by the photobleaching process. When the optical mask is realized, it is used to mask the light-sensitive photoresist layer when the photoresist layer is exposed to light. However, the photobleached layer, which is also sensitive to light, is now in turn made to be substantially unaffected by the exposure process. In this manner, the integrity of the optical mask resolution is maintained at its optimum, and densely integrated circuits can be processed and fabricated.

Abstract: A method and an apparatus are disclosed which are suitable for applying uniform coatings to integrated circuit (IC) wafers by means of chemical vapor deposition in a process suitable for use in mass production of IC wafers. The process introduces a first group of reactant gases into the vicinity of the wafers through at least one inlet. The number of inlets and the positions of inlets are selected to reduce the total variation in thickness produced on a batch of wafers to within preselected values of variations. The choices of pressure and temperature as well as the choice of gases in the first group are selected to optimize uniformity.

Abstract: A method is presented for accurately measuring an input signal's frequency components and the amplitude of those components. This is done by digitizing an input signal, passing it through a window, converting it into the frequency domain, and using the Fourier transform of the window to remove the effects of window from the input signal converted into the frequency domain.

Abstract: The capability of varying sizes of a dot in a printer is fully exploited to provide a gray scale image of superior quality. Errors in gray level are used to modulate the sizes of the dots in producing the image.

Abstract: A circuit in a synchronous detector system is provided to minimize and compensate for the errors induced by phase modulation and additive noise in the system. In one embodiment a first-order correction of such errors is achieved by equipping the synchronous detector system with a constant loop filter noise bandwidth and an RMS detector. A resolution filter passing the detected system signal to the RMS detector for correction is made to have a noise bandwidth identical to the loop filter noise bandwidth.

Abstract: A method of forming the proper metallization contacts in a multilayer epitaxy laser device is provided. By selecting the proper crystal plane orientation in etching nonplanar features like channels for the device, a differential etch rate in a free-etch can be effected to remove only selected portions of the top layer and to provide self-alignment in the metallization process.

Abstract: A method is provided to eliminate harmonic skip problems in a down-conversion system. The method makes use of the relationship between the frequency of the intermediate frequency signal and the harmonic number of the local oscillator signal with respect to the frequency of the frequency of the source signal. By monitoring and measuring corresponding changes in the intermediate frequency signal caused by predetermined changes in the frequency of the local oscillator signal, a determination of the proper local oscillator signal and the proper harmonic can be made using a processor. The proper frequency and harmonic can then be maintained by periodically checking the relationship between variables.

Abstract: A scheme for improving the decoding time of macroinstruction opcodes in a programmed computer is provided. By having a direct Instruction Jump Table responding to macroinstructions and a pipelined Address Jump Table responding to the same macroinstructions simultaneously, larger sequences of microinstructions are decoded in a minimum number of microcycles, thus resulting in a faster operating programmed computer.

Abstract: A method and apparatus is presented for calibrating instruments for time interval measurements, pulse width measurements, and rise and fall time measurements. The preferred method comprises generating two coherent pulses using a linear passive device. The coherent pulses are simultaneously a.c. coupled to two channels of, for example, a time-interval measuring instrument. The time interval between the coherent pulses passing through the instrument is measured at identical voltages on each signal. Then the coherent pulses are exchanged between the channels and a further interval measurement is made. The results of each of the measurements are compared and used to calculate calibration constants to correct systematic errors present in the instrument.

Abstract: A circuit for the conversion of an electrical input signal into an optical output signal is disclosed. A portion of the main beam from a laser diode that provides the optical output is reflected to a PIN diode with a glass pane. Linearization of the electro-optical conversion process over a wide frequency range is achieved through a feedback loop. For operation at frequencies higher than that of the feedback loop bandwidth, the various conversion factors for low and high frequencies can be additionally adapted.

Abstract: A method of forming the proper metallization contacts in a multilayer epitaxy laser device is provided. By selecting the proper crystal plane orientation in etching nonplanar features like channels for the device, a differential etch rate in a free-etch can be effected to remove only selected portions of the top layer and to provide self-alignment in the metallization process.