Sharp Kabushiki Kaisha Corporation

Megachips Corporation

Toshihide Miyake

Masanori Inamori

Zempei Tani

Yoshifumi Masuda

Toshihiko Shigenari

Shunro Mori

The optical position detection device includes a light irradiation unit that irradiates a target object with light, and a light receiving unit that receives reflected light from the target object. The light receiving unit includes a segmented photodiode in which a light receiving surface is two-dimensionally segmented into a plurality of light receiving regions, the segmented photodiode outputting a current corresponding to the intensity of light received by each of the light receiving regions; a light receiving lens that condenses the reflected light from the target object and forms an image of the target object on the light receiving surface of the segmented photodiode; and an arithmetic unit that detects a position of the target object in a two-dimensional direction orthogonal to the optical axis of the light receiving lens, based on the output currents corresponding to the respective light receiving regions of the segmented photodiode.

Apparatus and method for optical gesture recognition

A damping circuit includes two circuits. Each circuit has a PNP transistor, an NPN transistor, and a shunt resistor. The PNP transistors are connected in series to the NPN transistors through level shift stages. The PNP transistor and the NPN transistor have emitter functions of the same area. The shunt resistors are connected to the emitters of the NPN transistors. Both of the two circuits are connected to a coil in parallel in such a manner that the two circuits have opposite polarities to each other about the coil.

Damping circuit providing capability of adjusting current flowing

There are provided a first constant-current circuit and a second constant-current circuit, and a first resistor connected in series with the first constant-current circuit generates a band-gap voltage. The first constant-current circuit and the second constant-current circuit constitute a current Miller circuit, and a part of a current that flows through the second resistor connected in series with the second constant-current circuit is outputted as a constant current source. The constant-current power supply IC, which has the above-mentioned arrangement, is designed as follows: the first resistor and the second resistor have a predetermined line-width ratio that is determined in such a manner that if the respective line-widths vary by virtually the same value, a varied amount in the second constant current value that has been caused by a variation in the value of resistivity of the first resistor is cancelled by a varied amount caused by a variation in the value of resistivity of the second resistor. This arrangement is effective in compensating function and makes it possible to minimize the error on the constant current output due to deviations that occur during production.

Constant-current power-supply circuit formed on an IC

A log compressing circuit is arranged so that the clamping level is independent of the amplification factor of a first transistor for amplifying input current. The log compressing circuit includes the first transistor for amplifying input current, a compressing diode for log-compressing the amplified current, a clamp voltage generating diode serving as a source for generating a clamping voltage, and a second transistor for clamping the log-compressed voltage if the voltage goes beyond a predetermined clamp voltage. The second transistor has the same form as the first transistor and provides a collector connected to a cathode of the clamp voltage generating diode. The constant current is supplied to the second transistor from a constant current source.

Log compressing circuit providing capability of keeping clamp level

Transistors Q11 and Q12 constitute a first differential amplifier, their emitters are connected with each other by a resistor R1 and also connected respectively to constant-current sources CS11 and CS12. Transistors Q15 to Q17 constitute a second differential amplifier, and the collector of the transistor Q16 is connected with a current mirror 17. This current mirror circuit 17 is constituted by transistors Q18 and Q19 and resistors R3 and R4. The capacitor 22 is supplied with a current from the current mirror circuit 17, and its voltage is fed back through a buffer circuit 14 to the base of the transistor Q12 as a component of the first differential amplifier.

Filter circuit for integrated circuit

For use with an automatic focusing device, a semiconductor integrated circuit is provided for measuring distance having a light-detecting element for receiving light from an object, the distance to the subject is to be measured, and outputting a signal according to the distance from the object. The semiconductor integrated circuit is formed in one chip and includes a distance measurement arithmetic unit for forming digital distance measurement data inversely proportional to the distance to the object from the signal from the light-detecting element; a memory unit for writing therein two items of distance measurement data output from the distance measurement arithmetic unit with regard to two known distances in a calibration mode, and a data arithmeteic unit for computing an automatic focusing device control signal from the two items of distances measurement data stored in the memory unit and distance measurement data output from the distance measurement arithmetic unit in a distance measuring mode.

Semiconductor integrated circuit for measuring distance for automatic

In a semiconductor color sensor circuit with two photodiodes having mutually different wavelength sensitivity characteristics, the ratio of numbers or areas of two types of transistors for logarithmic compression of signals from these photodiodes is adjusted so that errors in output voltage due to changes in temperature can be reduced and the dynamic range of illuminance of incident light can be enlarged.

Semiconductor color sensor detection circuit

A semiconductor switch circuit includes a switching transistor circuit having switching transistors connected in two stages, a follower circuit comprising a condenser for integration, a power source circuit, the switching transistor circuit connected between the follower circuit and the power source circuit, and a switching transistor connected as the second stage of the switching transistor, circuit such that each of the base and the emitter of the switching transistor is connected to a resistor and the resistor is connected to an output terminal of the follower circuit for generating an output whose level equals the level of the collector of the switching transistor.

Semiconductor integration circuit

An electronic shutter control circuit comprises a photo-conductive material producing a signal to be applied to the first transistor, a second transistor having a base connected to its collector, the second transistor being serially connected to the first transistor, a third having a base transistor connected to the collector of the first transistor having a base, a fourth transistor connected to its collector, the fourth transistor being serially coupled to the third transistor, a current supplier circuit connected to the fourth transistor, a capacitor serially coupled to the third transistor, and a comparison circuit connected to the capacitor for detecting a charge amount condensed by the capacitor and for providing shutter operation signals used for operation of a shutter mechanism.

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Nara, Japan

Toshihide Miyake