Abstract: A new sensor called differential reticle grating displacement sensor is proposed for the first time. This invention is sourced from the idea of vernier caliper. Using the scale differential of two scaled parts with relative motion, in the condition of the same reticles changes of some physical parameter can be formed between the reticles. It can gain more pulse signals, which has identical effect of pulse interpolation or frequency doubling. And the goal of improving resolution can be attained. The design idea, the working principle, the wave analysis, the precision analysis and the experiment effect of the sensor are introduced. The research result shows that thickness, spacing and number of the reticles can affect directly the number, amplitude, wave shape, accuracy and other characteristic of the pulse signal. It will play an important role to improve the traditional grating type displacement sensor technology.

Key words: Differential grating, Displacement sensor, Experiment effect