Low-loss Quartz Crystal Optical Filter Design

The quartz crystal optical filter is an important optical components,it has advantages of mading easy, inexpensive, high transmission and no restrictions on the using band.But in real applications,The spectral ranges and passband half-width of this structure is not ideal,and the large central maximum is surrounded by some secondary,These sideband energy are greatly reduced through the filter to observe the image contrast;and the number of polarizers affects the level of tranmission,which will be related to how to improve the transmission of emergent light and reduce these sideband energy problem.After many research on the crystal optical filter, we study the crystal filter, analyzing facters of the main tranmission and half-width passband.On this basis,we have studied the new low-loss quartz filter theoretically and experimentally.The full text mainly includes four chapters given as follows.In the first chapter, we introduce the development and present research of the optical filter. The issue of significance and the work of this paper is also introduced.In the second chapter,Filter performance parameters and classification. A few fundamental theories about the optical filter are introduced. And the principle of some typical filter was introduced.In the third chapter,The third chapter is the properties of quartz crystal filters,we mainly describe the quartz crystal birefringent filter and optical rotation filter.the optical birefringent effect and the optical rotatory dispersion effect of the quartz have been analyzed,Using muller Matrix,we deduce the transmission equations of single-stage and multi-stage filterThe fourth chapter is the improvement design of Multi-stage filter and is also the most important parts in this paper.Against existing sideband energy around the main tranmission in reality,We have designed quartz crystal filter of enhancing sideband energy.Then,Against unsatisfactory transmittance of the main tranmission,we use wave plate,crystaland the combination of polarizer to design the low quartz crustal filter,deduce formula of the new design.,and make transmission curve.With the comparison to original design,it shows that,the new design is possible to reduce ideband energy and the effect of loss.In this paper,we have used two design proposals of quartz crystal birefringence effect and rotation effect,both of them have achieved improved results.In the fifth chapter, the spectral transmission of the optical quartz filter was measured by a spectrophotometer (UV-3101PC).The new design of crystal rotation filter was measured.According to the new design principle of crystal rotation filter, We manufacture the test samples and tested on the transmission spectrum.The results coincide with the theoretical curve,which verfies the feasibility of this new designs.