SU1520472A1 - Shaper of optical signals - Google Patents

Abstract

The invention relates to optical instrument making and can be used in optical communication lines, in measurement technology for converting electrical signals into optical ones. The aim of the invention is to increase the stability of the amount of radiated power. The stability of the radiated power is achieved by significantly reducing the oscillations of the injection current corresponding to a given radiation power of a semiconductor radiator by introducing a feedback loop into the device. 2 Il.

Description

The invention relates to optical instrument making and can be used in optical communication lines, in measurement technology for converting electrical signals to optical signals.

The purpose of the invention is to increase the stability of the radiated power.

Figure 1 shows the functional diagram of the optical signal shaper; 2 is an electrical circuit of a current limiter.

The device contains a semiconductor emitter 1, a voltage source 2, a first resistor 3, a current limiter 4, a switch 5 with a control input, a second resistor 6, a third resistor 7, a fourth resistor 8, a photodiode 9, a fifth resistor 10, a sixth resistor 11, The first transistor 12, the second transistor 13, the seventh 14 and the eighth 15 resistors.

The shaper works as follows.

In the initial state, when there is no signal at the control input of switch 5, the circuit: output of voltage source 2, resistor 3, semiconductor radiator 1 flows a bias current determining the minimum power of semiconductor radiator 1. The bias current of semiconductor radiator 1 is determined by the value of the second resistor 6 taking into account the residual voltage on the switch 5 and the shunting effect of the current limiter 4, which is determined by the magnitude of the initial current of the photodiode 9 embedded in the semiconductor emitter 1. Working The voltage on the photodiode and the bias voltage at the input of current limiter 4 are determined by a divider consisting of a fifth resistor 10, a third resistor 7, and a fourth resistor 8c. The shunt effect of the current limiter is also determined by the value of resistor 11 (Fig. 2) for increase the speed of which included the seventh 14 and eighth 15 resistors.

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When a modulating signal is applied to the control input of the key 5, the key closes and the amount of current flowing through the semiconductor emitter 1 increases and is determined by the first resistor 3 and the shunt effect of the current limiter 4, and the semiconductor emitter t emits optical power.

The change in radiation power resulting from external influences or changes in supply voltage leads to a change in the current of the photodiode 9 embedded in the semiconductor emitter 1, thus changing the base injection current of the first transistor 12, and at the same time shunt the semiconductor emitter one.

An increase in the radiation power of the semiconductor emitter 1 leads to an increase in the current of the photodiode 9, an increase in the current flowing through the current limiter 4, and an increase in the shunting effect on the semiconductor emitter 1. Conversely, a decrease in the radiation power of the semiconductor emitter 1 decreases the photodiode current, decreases the current flowing through the current limiter 4, and reducing the shunting effect on the semiconductor emitter 1

The stability of the magnitude of the radiated power in the range of external influences and changes in the magnitude of the supply voltage is reduced due to

a dramatic reduction in injection current oscillations corresponding to a given radiation power of a semiconductor radiator 1.

Claims (1)

Invention Formula An optical signal shaper that contains a key with a control input, a semiconductor emitter, the anode of which is connected to the first resistor, and the cathode is connected to the common bus, to which the common output of the key and the first one are connected; voltage source, the second output of which is connected to the first resistor, the second resistor, which replicates with the fact that, in order to increase the stability of the radiated power, a photodiode, a current limiter, three resistors, a current limiter input are connected to the anode semiconductor emitter and the second resistor, which is connected to the key of the switch with a second output, connected to the second source of the voltage source are connected in series the third, fourth and fifth resistors, the latter connected to the second output the common busbar, the photodiode is connected in parallel to the fourth resistor, and the photodiode anode is connected to the third resistor and to the control input of the current limiter, and the key input is connected to the second output of the voltage source, the common output of the current limiter is connected to the common busbar (riel FI.2