Abstract: A vertical cavity surface emitting laser having a planar structure, having an implantation or diffusion at the top of the mirror closest to the substrate or at the bottom of the mirror farthest from the substrate, to provide current confinement with the gain region, and having an active region and another mirror formed subsequent to the implantation or diffusion. This structure has an implantation or diffusion that does not damage or detrimentally affect the gain region, and does provide dimensions of current confinement that are accurately ascertained. Alternatively, the implantation or diffusion for current confinement may be placed within the top mirror, and several layers above the active region, still with minimal damage to the gain region and having a well-ascertained current confinement dimension.

Abstract: A vertical cavity surface emitting laser having a planar structure, having an implantation or diffusion at the top of the mirror closest to the substrate or at the bottom of the mirror farthest from the substrate, to provide current confinement with the gain region, and having an active region and another mirror formed subsequent to the implantation or diffusion. This structure has an implantation or diffusion that does not damage or detrimentally affect the gain region, and does provide dimensions of current confinement that are accurately ascertained. Alternatively, the implantation or diffusion for current confinement may be placed within the top mirror, and several layers above the active region, still with minimal damage to the gain region and having a well-ascertained current confinement dimension.

Abstract: A turbidity sensor is provided with two light sensitive components or elements. One light sensitive component is displaced from a light source, such as a light emitting diode, so that a fluid can pass therebetween. A second light sensitive component is disposed within a common compartment with the light source so that it can measure the intensity of light provided by the light source. The light source and the second light sensitive components can be individual elements, or chips, within a common component package. A regulator is provided to control the magnitude of current provided to the light source so that its light intensity can be regulated. In this manner, the intensity of light emitted by the light source, such as a light emitting diode, can be controlled regardless of the aging of the LED, the variability of LED characteristics and the temperature surrounding the LED.

Abstract: A vertical Hall element is formed within the epitaxial layer of a semiconductor and isolated from other components by a P type isolation diffusion. A position defining diffusion is used to accurately locate a plurality of openings within the position defining diffusion where contact diffusions are made. The position defining diffusion is made simultaneously with the base diffusion for transistors within the integrated circuit and the contact diffusions are made simultaneously with the emitter diffusion of transistors within the integrated circuit. Five contact diffusions are provided on the upper surface of the epitaxial layer and generally aligned within the region defined as the Hall element by the isolation diffusions. The center contact is used to provide electrical current flowing through the Hall effect element. Electrical current is split and flows to the two end contact diffusions.

Abstract: A fiber optic sensing apparatus is provided to measure the relative reflections of two temporarily displaced signals. One of the signals is a reference signal and the other signal represents the magnitude of a sensed variable. A reference mirror is disposed at a preselected position along an optical fiber between a transmitter/receiver and a sensor mirror. The transmitter provides an energy pulse into a first end of the optical fiber. When the energy pulse encounters the reference mirror, a first portion of the energy pulse is reflected back toward the receiver which is located at the first end of the optical fiber. The remaining portion of the energy pulse continues toward the sensor mirror. A second portion of the energy pulse is reflected by the sensor mirror. The second portion is of a magnitude that is analogous to the sensed parameter. Fiber optic delay lines are provided between the reference mirror and the transmitter/receiver and also between the reference mirror and the sensor mirror.

Abstract: A temperature compensation system for semiconductor logic gates where the temperature compensation is accomplished by two depletion mode FET's in electrical series relationship is disclosed. One of the FET's is adapted to operate in its triode region of operation and the other in its saturation region of operation.

Abstract: A data transmission link including a transmitter for acquiring conducted electrical data and transmitting electromagnetic radiated wave data such as optical data corresponding to the conducted electrical data, a receiver for receiving the electromagnetic radiated wave data and generating conducted electrical data corresponding to the radiated wave data and at least one wave conduit such as fiber optic data transmission cable for transmitting the radiated wave data from the transmitter to the receiver is disclosed. In one arrangement, the transmitter includes a light emitting device which is driven by an output driver responsive to the electrical data accepted by an input gate.

Abstract: A differential stage of an amplifier includes an input transistor and a second transistor with a significantly greater emitter cross-sectional area than the input transistor. Quiescent emitter current is divided between the two transistors in substantially the same ratio as the emitter cross-sectional areas so that the emitter current densities are substantially equal.

Abstract: Disclosed is an optical data bus employing a passive optical coupler. The optical coupler includes a scrambler rod which is rectangular in cross section and employs solid substantially inflexible side arms which are also rectangular in cross section. The side arms include a mirrored prism to bend the light path and permit separation of the ends of the distribution side arms so that flexible fiber bundles may be attached to the ends of the distribution side arms.

Abstract: A method and apparatus for altering the apparent electrical characteristic of a distributed electrical component in an integrated circuit is disclosed. In one form a distributed load resistor is sunk into a parallel distributed guard resistor. The mutual distributed capacitance between the distributed load resistor and the parallel distributed guard resistor is substantially greater than the distributed capacitance between the distributed load resistor and any other electrical component. A follower circuit for driving the voltage across the parallel distributed guard resistor by the voltage across the distributed load resistor is provided.