SU1603200A1 - Position sensitive sensor of optical radiation - Google Patents

Abstract

This invention relates to instrumentation technology. The purpose of the invention is to expand the dynamic range of a position-sensitive sensor based on current-to-voltage transducers (PTN). The position-sensitive optical radiation sensor contains a four-quadrant photodetector and an electronics unit comprising five PTNs, a sum-difference device, an inverter and four resistors connected from the output of the inverter to the inputs of four PTNs, and the value of the resistors is four times PTN 1 il.

Description

The invention relates to instrumentation technology and can be used in trace ides and test instrumentation systems based on positional photodiodes.

The purpose of the invention is to expand the dynamic range of the sensor.

The drawing shows the functional diagram of the sensor.

The sensor consists of a four-quadrant photodetector 1, the photodiodes 1.1-1.4 of which are connected to the inputs of the transducer - current - voltage (ПТН) 2-5. The signals from the outputs PTN 2-5 arrive at the inputs of the sum-difference device 6, which generates the positional signals.

The common substrate of the photodiodes is connected to the input of the fifth ПТН 7, the output of which is connected to the input of the inverter 8 voltage, and the output of the inverter 8 through the resistors 9-12 is connected to the photodiodes 1.1-1.4, and the ratings of the resistors 9-12 are four times higher the resistor value of the first PTN, and the legs-1 of this resistor, in turn, are chosen to be sufficiently small in order to ensure the efficiency of the PTN 7 over the entire dynamic range.

The device works as follows.

At the input of each of the PTN 2-5 current is generated corresponding to the CO

YU

3t6

From photodiodes 1.1–1.4 of the photodiode 1. Through the resistors 9–12, the inputs of the PTN 2–5, respectively, receive a current equal in magnitude to the average

current value of all photodiodes of photo receiver 1, and in the opposite direction to it.

As a result, each of the converters 2–5 converts only the current of the difference by the current corresponding to the photodiodes 1.1 ± 1.4 and is more than the average value of the current of all photodiodes.4

Photodiode substrate current 1 1

- The current of the 1st photodiode photocurrent I; - Eshshka 1.

For all the ratio

PTN

and

. dbix

2-5 and 7 holds -lekR, where Ugbix

-

output voltage PTN; Igji - PTN input currents; R is the value of resistors in the PTN feedback circuit (R,

R

.3

Ra) RS 7

 For the second PTN on the value of ,, 7

output takes

-I

R7

P

 Signal

1;

"M

7 "

--g:

.inverter output "t

iib - - -j- t Subject to that.

what r

Rio

R, R cr 4K.; F and the potentials on the PTN odes are equal to zero, the currents of the compensation at the inputs of the PTN 2-5 take the form4

i; -Rr

- “MT

iznb ... Зк 4Rt

one

Thus, the compensation current arising in each of the PTN 2-5 is equal to the average value of the currents of all the photodiodes of the photodetector 1 and has the opposite direction, i.e. each of PTN 2-5 converts current

PTN

I.

The implementation of the device according to the above scheme makes it possible to exclude from the PTN 2-5 conversion a constant current component that does not carry information about the position of the energy center of the severity of the detected radiation, which expands the dynamic range of the sensor. In this case, the optimal ratio of nominal;

20

th

25

PTNs 2-5 and 7 R2

R,

4 him

thirty

5 5 7 is equality

dynamic range

photodiodes and PTN.

Claims (1)

Invention Formula A position-sensitive optical radiation sensor containing a four-quadrant photodetector made on the basis of four photodiodes on a common substrate, four current transducers - voltage with the same conversion factors and a total difference device, while the photodiode outputs are connected to current-voltage transducer inputs The outputs of which are connected to the total difference device, characterized in that, in order to expand the dynamic range of the sensor, a fifth converter is introduced into it l current - voltage, inverter and four resistors, with the output of the photodiode substrate connected to the input of the fifth inverter current - voltage, the output of which is connected to the input of the inverter, the output of the inverter through four resistors connected respectively to the inputs of each of the four converters current - voltage, whereby the value of each input resistor is four times the conversion factor of the fifth current-voltage converter. 35 40 Compiled by E. Makolkin Editor A. Otar Tehred M. Didyk Proofreader A. Osaulenko Order 3377 Circulation 429 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. 4/5 Production and Publishing Combine Patent, Uzhgorod, st. Gagarin, 101 Subscription