Abstract:
A channel isolation region 42 is formed over the entire width of an N-type silicon substrate 41, and photothyristors, in each of which an anode diffusion region 43, a P-gate diffusion region 44, a cathode diffusion region 45 are formed parallel to the channel isolation region 42 over almost the entire width of the N-type silicon substrate 41, are formed in a left-hand portion 40a and in a right-hand portion 40b and are wired inversely parallel. Thus, the inter-channel movement of residual holes during commutation is restrained by the channel isolation region 42, by which commutation failure is suppressed to improve a commutation characteristic. Further, an operating current large enough for controlling a load current of approx. 0.2 A is obtained although a chip is divided by the channel isolation region 42. Therefore, using this bidirectional photothyristor chip makes it possible to implement an inexpensive SSR with a main thyristor eliminated.
Abstract:
A Schottky barrier diode 44 is formed between a P-gate diffusion region 33 and an N-type silicon substrate 31 in a photothyristor on a CH1 side and a photothyristor on a CH2 side. With this arrangement, the injection of minority carriers from the P-gate diffusion region 33 to the N-type silicon substrate 31 is restrained to reduce the amount of remaining carriers, and an excessive amount of carriers remaining in the N-type silicon substrate 31 during commutation has a reduced chance of moving toward the opposite channel side, allowing the commutation characteristic to be improved. Therefore, by a combination with an LED, there can be provided a light-fired coupler for firing and controlling the load.
Abstract:
A channel isolation region 42 is formed over the entire width of an N-type silicon substrate 41, and photothyristors, in each of which an anode diffusion region 43, a P-gate diffusion region 44, a cathode diffusion region 45 are formed parallel to the channel isolation region 42 over almost the entire width of the N-type silicon substrate 41, are formed in a left-hand portion 40a and in a right-hand portion 40b and are wired inversely parallel. Thus, the inter-channel movement of residual holes during commutation is restrained by the channel isolation region 42, by which commutation failure is suppressed to improve a commutation characteristic. Further, an operating current large enough for controlling a load current of approx. 0.2 A is obtained although a chip is divided by the channel isolation region 42. Therefore, using this bidirectional photothyristor chip makes it possible to implement an inexpensive SSR with a main thyristor eliminated.
Abstract:
An optical detection device includes a light emitting element, which is an area sensor, a light emitting lens part for irradiating an object to be measured with a bundle of emission rays emitted from the light emitting element, a light receiving lens part for condensing reflected light from the object, a light receiving element for detecting reflected light from the object condensed by the light receiving lens part, and a signal processing section for processing a light-reception signal from the light receiving element. Based on the light-reception signal from the light receiving element, the signal processing section detects at least one of an x-coordinate or a y-coordinate of the object on an x-y coordinate plane from at least one of a light-spot position or a light-spot shape on the light receiving element.
Abstract:
A lens frame, made from metal, retaining a light-emitting lens and a light-receiving lens is retained between a second mold and a third mold both of which are made from light-shielding resins. Anchors are formed by filling light-shielding resin for forming the third mold into fixing slots formed in an upper surface of the second mold and through holes formed in the lens frame. Since the lens frame is made from metal, thermal expansion of the lens frame is hardly caused by ambient temperature changes and self-heating. This causes little difference in the amount of change in difference between the lenses. Further, the lens frame is fixed with anchors between the second mold and the third mold. This suppresses the occurrence of sliding caused by difference in thermal expansion coefficient between the lens frame and the second and third molds.
Abstract:
Si.sub.3 N.sub.4 having high humidity resistance is used as a surface protecting insulating film covering a metal layer. At a bonding pad portion where metal layer is directly exposed, coverage is provided by anti-corrosion metal portion consisting of a titanium-tungsten alloy layer and gold layers. At a signal processing circuit portion, light intercepting structure and interconnection are provided similarly by titanium-tungsten alloy layer and gold layer. Thus humidity resistance of a photodetector element containing a circuit element is improved, and the gold layer allows direct die-bonding of a laser chip or the like. Further, since light intercepting structure and interconnection can be provided at the signal processing circuit portion simultaneously with the formation of gold layer for the bonding pad portion, the number of manufacturing steps can be reduced.
Abstract:
A lens frame, made from metal, retaining a light-emitting lens and a light-receiving lens is retained between a second mold and a third mold both of which are made from light-shielding resins. Anchors are formed by filling light-shielding resin for forming the third mold into fixing slots formed in an upper surface of the second mold and through holes formed in the lens frame. Since the lens frame is made from metal, thermal expansion of the lens frame is hardly caused by ambient temperature changes and self-heating. This causes little difference in the amount of change in difference between the lenses. Further, the lens frame is fixed with anchors between the second mold and the third mold. This suppresses the occurrence of sliding caused by difference in thermal expansion coefficient between the lens frame and the second and third molds.
Abstract:
An LED drive circuit for driving an LED by input of an alternating voltage, the LED drive circuit being capable of connecting to a phase control dimmer. The LED drive circuit is provided with a current extractor for continuing to allow current to flow into the phase control dimmer so that a phase control element inside the phase control dimmer does not switch off before the alternating voltage reaches 0 V after the phase control element inside the phase control dimmer switches on and the LED emits light.
Abstract:
A circuit-incorporating photosensitive device comprising: an SOI wafer including a first silicon substrate, a second silicon substrate, and an oxide film; a photodiode formed in a first region of the SOI wafer; and a signal processing circuit formed in a second region of the SOI wafer, wherein the photodiode includes a photosensitive layer formed of an SiGe layer.
Abstract:
The circuit-integrating light-receiving element of this invention includes: a semiconductor substrate of a first conductivity type; a first semiconductor layer of a second conductivity type formed over the semiconductor substrate; a first semiconductor layer of the first conductivity type for dividing the first semiconductor layer into semiconductor regions of the second conductivity type; light-detecting sections being constituted by the divided semiconductor regions and underlying regions of the semiconductor substrate, a divided photodiode being composed of the light-detecting sections; a second semiconductor layer of the second conductivity type formed only in the vicinity of the first semiconductor layer of the first conductivity type functioning as a division section of the divided photodiode and within the regions of the semiconductor substrate forming the respective light-detecting sections; and a second semiconductor layer of the first conductivity type formed in a surface region of the first semiconductor layer of the second conductivity type including the division section so as to cover an upper part of the second semiconductor layer of the second conductivity type.