Light cutting device for optical chopper and controlling method thereof

Abstract

The invention relates to a light cutting device for an optical chopper and a controlling method thereof. According to the device provided by the invention, a metal light barrier is arranged in the energized electromagnetic coil, the direction of current flowing from the metal light barrier is vertical to the direction of field generated by the electromagnetic coil, the light barrier moves along the set sliding groove under the action of electromagnetic force. The direction of the current flowing through the electromagnetic coil or the light barrier is changed as per the preset frequency, so that the metal light barrier can move back and forth along the sliding groove. The light barriers are arranged in the front and back of the light through hole, the movement of the light barrier can control whether the incident light passes through the optical chopper light cutting device or not, so as to accomplish the modulation of incident radiant. The light barrier is enabled to pass through the position between the coupling luminous diode and the phototriode during movement, so as to collect the modulation frequency of the optical chopper light cutting device. The adjustment of radiation modulation frequency can be accomplished by only one output control of the controller; cost is reduced, practicability and flexibility are increased, and application range is enlarged; measurement accuracy is improved, and utility difficulty of an operator is decreased.

Description

technical field

[0001] The invention relates to an optical chopper, in particular to an optical chopper light chopping device and a control method thereof. Background technique

[0002] Optical chopper, also known as optical chopper, is an instrument that modulates the light emitted by a continuous light source into an alternating optical signal, which is convenient for frequency-selective amplification and coherent detection after photoelectric conversion. In addition to modulating the measured light, the chopper can also output a reference voltage square wave synchronized with the modulation frequency as the reference signal of the lock-in amplifier. It is used in laser, optical or microwave measurement systems using lock-in amplifiers. An essential instrument in signal measurement.

[0003] In a traditional optical chopper, a motor drive circuit usually controls the rotation of the motor to drive the chopper with a light hole to rotate, thereby completing the modulation ...

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