Industrial - Grating Displacement Sensor - Agent [Weikewei]

grating sensor It consists of a light path system, a ruler light shed (main light shed), and an indicator light shed. Usually, the indicator grating is much shorter than the scale grating, but both are engraved with the same density lines. When measuring displacement, indicate that the light flip is fixed and the ruler is stationary, and the light shed is moving. In length measurement applications, the scale grating and indicator grating are referred to as measurement gratings.

According to the optical path direction of the metrological grating, the grating displacementsensorThere are two types: transmissive and reflective.

1. Transmissive grating传感器form

Transmissive grating sensorComposed of a light source, lens, ruler, grating indicating light shed, and optoelectronic components.

The light emitted by the light source is condensed by a lens to form a parallel beam that is directed towards the scale grating. The scale grating transmits the light and illuminates the indicator grating, forming Moir é fringes. When the scale grating moves relative to the indicator grating, the photoelectric element receives the light signal of the Moir é fringes alternating in brightness and darkness, converts it into an electrical pulse signal, and displays it digitally, thereby achieving the measurement of the movement distance of the scale grating.

The light source usually uses tungsten filament bulbs or arsenide tungsten light-emitting diodes. Tungsten filament bulbs have a large output power and a wide working range (-40 ° C~+130 ° C), but their service life requires regular replacement. Gallium arsenide light-emitting diodes have a lower output power than tungsten filament bulbs and a working range (-66 ° C~+100 ° C). The light they emit is similar to infrared light, close to the sensitive wavelength of silicon phototransistors. When combined with silicon phototransistors, they have a faster pulse response speed and can reduce thermal power consumption.

Optoelectronic components commonly use phototransistors or photovoltaic cells. An amplifier is often connected to the output terminal of the optoelectronic component to amplify the signal and improve its anti-interference ability.

2. Reflective grating传感器form

The light emitted by the light source is condensed by a fragrance mirror to form a parallel beam that passes through the indicator grating at a certain angle and is directed towards the scale grating. The scale grating is opaque, and the light is reflected on the scale grating to form Moir é fringes with the indicator grating. The Moir é fringe light is then reflected by the mirror, focused by the lens, and directed onto the photoelectric element to achieve displacement measurement.