Device and method for generating positive index pulse light signal with specified parameters

Abstract

The invention discloses a parameter-specified positive index pulse optical signal generating device and method. The device comprises a positive index signal generating module, an electro-optical conversion module, an output optical signal monitoring module and a power supply module; a positive index electric signal is generated by using a resistance transmission cable network method; a light emitting diode of which the P-I (power-current) linearity is less than 1 percent and the linear range is greater than 100 times is driven to light in a mode of summing a pulse current prebias and a positive index current signal; the linear conversion between the electric signal and an optical signal is realized; the problem that the positive index pulse optical signal is difficult to generate is finally solved; a feasible method for monitoring the characteristics of an output optical signal online is given according to a system driving principle. By using the method and the device, the positive index pulse optical signal with the positive index character parameter alpha of greater than 20mu s <-1> and the index character remaining range of greater than 100 times can be generated; the device and the method have the capacity of monitoring the characteristics of the output optical signal online; an analogue optical signal source can be provided for the research work, such as laboratory standardization, debugging, calibration and evaluation, of a photoelectric measurement system aiming at index signal measurement.

Description

technical field [0001] The invention relates to a light source used for laboratory calibration and debugging of a photoelectric measurement system for the purpose of index signal measurement, in particular to a method capable of generating a positive index pulse light signal with specified parameters and monitoring the characteristics of the output light pulse signal on-line in real time . Specifically, the method can generate a pulsed optical signal whose intensity-time spectrum conforms to a positive exponential rise relationship and evaluate the exponential characteristics of the output optical signal. Background technique [0002] In the operation diagnosis process of nuclear reactors or large-scale nuclear reactors, it is necessary to diagnose the operating status or design performance of nuclear devices by measuring the pulse neutron or gamma time intensity spectrum. This type of time intensity spectrum usually has an exponential growth law, that is, the pulse intensit...

AI Technical Summary

Problems solved by technology

The modulation curve of this type of light source is nonlinear, and it is impossible to generate a pulsed light signal that conforms to the exponential characteristic.

The third type is the internal modulation light source based on semiconductor light-emitting devices. This type of light source is mainly used in the field of optical communication. The modulation signal is generally a sine (cosine) signal, which cannot directly generate a pulsed optical signal that conforms to the exponential characteristics.

[0004] At the same time, the modulation method of the internally modulated light source is generally to superimpose a continuous modulated electrical signal on the DC bias. This modulation method has two serious defects for generating positive index pulsed optical signals. First: DC bias causes the semiconductor light-emitting device to always be on , which in turn causes the cathode fatigue effect of the photomultiplier device for low-light measurement to be tested, and cannot work normally, which is not conducive to the generation of positive index pulsed optical signals that can be used in practice; secondly, the use of DC bias will greatly limit the dynamic range of the system

In addition, the commonly used voltage drive and triode common emitter current drive have large non-linearity, and it is impossible to realize the linear conversion between the positive exponential electrical signal and the optical signal.

Images