SU1229590A1 - Photosensor - Google Patents

Abstract

The invention is concerned with the detection and processing of electromagnetic radiation in the optical wavelength range and can be applied to control the direction of optical rays. The purpose of the invention is to expand the functionality and simplify the photo sensor. The photo sensor contains an optical unit 1, a four-quadrant photodetector 2 with cross-arranged triangular photo cells 3-6, which are connected through corresponding differential amplifiers 7 and 8 with the first 9 and second 10 threshold elements, the outputs of which are connected to the execution units 11 and 12. At the same time, the photo cells 3-6 are connected to a four-channel voltage follower 13 (the emitter follower is connected to the output with an adder 14, in which the sum occurs (L 09 CO o

Description

1229590

An electric signal whose pickup threshold chooses the value of which is proportional to the luminous flux. The sum signal is applied to the threshold element 15, pic from the insensitivity condition of the photo cells 3-6 to the background highlights.

The invention relates to the field of detection and processing of electromagnetic radiation in the optical wavelength range and can be applied to control the direction of optical rays incident on a radiation receiver.

The purpose of the invention is to expand the functionality and simplify the device.

The drawing shows the functional diagram of the device.

The photo sensor contains an optical unit 1, a four-quadrant photodetector 2 with crosswise located triangular photo cells 3-6, which are connected in a differential circuit and connected to the corresponding inputs of differential amplifiers 7 and 8, the outputs of which are connected to threshold elements 9 and 10, the outputs of which respectively, they are connected to executive units 11 and 12. At the same time, photocells 3–6 are connected to a four-channel voltage follower (emitter follower) 13, the output of which is connected to an adder 1 4, tory its output connected to the third threshold element A 15.

The device works as follows.

When focusing the light spot in the center of the photodetector signal, postapions on differential amplifiers 7 and 8 from oppositely located photocells 3, 5 and 4, 6, is equal to zero, since these photocells are switched on in a differential scheme, due to which background highlights are also zero. The threshold for triggering the threshold elements 9 and 10 is selected based on the condition of the required sensitivity of the photo sensor to the offset of the light spot.

which horn selects

with photocell insensitive condition 3-6 to ambient light.

At the same time, from the photocells 3, 5 and 4, 6, the signals arrive at a four-channel repeater 13 voltage, which is connected by its outputs: to an adder 14, in which the sum of the electric signal occurs, the value of which is proportional to the light flux. The sum signal is applied to a threshold element 15, the trigger threshold of which is selected from the insensitivity condition of the photo cells 3-6 to the background highlights.

When the direction of the optical rays changes, for example, due to the movement of the light of the tracking object, the light spot will shift in some direction from the center of the photodetector. In this case, one or both pairs of photocells 3, 5 and 4, 6 turn out to be illuminated differently, which leads to the appearance of an error signal taken from the outputs of the photo cells. The error signal through the amplifiers 7 and 8 and the threshold elements 9 and 10 is supplied to the executive units 11 and 12, which orient the photodetector so that the light spot is in the center of the photodetector. At the same time, the total signal, removed from the photocells 3, 5 and 4, 6, will be transmitted through the channel of registration of the luminous flux to the threshold element 15.

The invention makes it possible to additionally measure the power of the light flux while retaining the possibility of detecting the presence of a light spot, which expands the functionality of the device, as well as significantly simplifies the design of the photosensor, which reduces its reliability.

Claims (1)

Invention Formula A photo sensor containing an optical unit, a four-phase quadrant photo3 12295904 receiver, opposite to photoelectric expansion whose cops are connected through co-capabilities and simplifications, the channel The corresponding differential usi-registrations of the light flux are the executors with the first and second thresholds, in the form of four-way repeaters, the outputs of which are a connection voltage detector whose inputs are they are connected to the executive units, ka are connected to the photocell, and they register the registration of the luminous flux; the third threshold element is connected to the third threshold element, by the cop.