Briefly introduces the lighting requirement of car headlamp,narrates the surveying method of the upper beam,lower beam and group lamp′s character,also the train thought of confirming and how to make the light and shade closing line.

According to the third order aberration theory of binary optical element,the optical coupler system with one diffractive surface,telecentric optical path structure in the object space is shown with calculation and optimization of optical design software ZEMAX,whose operating wavelength is(0.

This paper uses an object telecentric beam path in a diameter measurement system, designs a data acquisition circuit ,and presents a accuracy measure method with polynomial interpolation.

The tracking precision is got by measuring the far-field facula posit.

The heat character and far-field facula of liquid laser with single gain host and double gain host at the same gain length were simulated,and then compared.