Broadband Optical Thin-film Achromatic Phase Retarder

Phase retarders are important optical components that introduce a phase shift between orthogonal and linearly polarized components of light transmitted through them. Fitted with other polarimetric elements, they can realize modifying of light and controlling of polarization states.λ/4 wave plate andλ/2 wave plate are more being applied at present, theλ/4 wave plate is much used for changing lineary polarized light into circularly polarized light or elliptical polarized light (produce 90°phases defer) , also or transforms elliptical polarized light into lineary polarized light;λ/2 wave plate(produce 180°phases defer) can to revolve polarization plane of lineary polarized light . We can speaking, Almost all the local which applied the polarized light s technology can't be seprated from the phase retarder.The routine phase retarder is made from double refraction material, since the material s birefringence has relation with the wavelength , makes the phase defer amounts have strict correspondence relation also with wavelength , the routine phase retarder is used for unitary wavelength as a result much ,so it bring about a lot of trouble when being used. But the achromatic phase retarder greatly weakde the dependency relationship between phase retarder and wavelength , can be used for bigger spectrum range.The achromatic phase retarder, can be divided into two major kinds according to the mechanical design: double refraction achromatic phase retarder and total internal reflection achromatic phase retarder.The double refraction achromatic phase retarder is made of apophyllite, there is so little apophyllite with use-value in nature , and until now have not discovered other materials to replace apophyllite , so it is difficult to extend. We can also constitute the achromatic phase retarder from two kinds or three kinds of double refraction material besides, but to every kind of material of combination element, whose thickness demands to have higher accuracy equally , this brings greatly difficulty to fabrication.The total internal reflection achromatic phase retarder is an rhomb-type phase tearter which according to total reflection phase change theory to design. We devide this kind of retarder by the structure as following: (1) Fresnel rhomb-type (2) Mooney rhomb-type (3)Rectangle prism compound (4) Achromatic implement J (AD-1) and achromatic implement 2 (AD-2) (5)Oblique incidence rhomb-type etc.The total internal reflection achromatic phase retarder is a kind of simple , stable achromatic phase defer implement , among so many retarders , Fresnel rhomb-type phase retarder are applied more. Though total internal reflection achromatic phase retarder has the more better achromatism than the double refraction achromatic phase retarder, but people defers accuracy and the achromatism with the development of Laser Technology, face to face.To medium, already basically, film optics characteristic property research complete, and has formed thin film optics new discipline in this one optics to the century in the sixties. The polarization characteristic property to the optical thin film and their applicative research news report mimicking a component going ahead in polarized light increases by gradually in the 70's, on the international , this grows tendency continuing for till 90's , this field studies the activity is still very active during the past the past few years.Because of optics dielectric film can be equivalent into a dichroic linear polarized device and a phase retarder when the light leanly incident into a surface of optics dielectric film , so we can steam optics dielectric film into device s surface to improve the accuracy of phase defer. The reflecting dielectric film phase retarder, is to point to the component using the certain place reflecting but making to come into being between two each other orthogonal component of the polarized light reflecting without the transmission method to there is difference between.The thesis first sets off from the development history of optics of thin film , and introduces some information of the optics of thin film which from the foundation to nearest development. Have introduced the optics of thin film's electromagnetic theory -Maxwell equation, and then introduced two kinds fundamental method of film s design, vector law and admittance matching method .Third chapters have introduced total reflection phase transition theory firstly , this has been the rationale of the total internal reflection phase retarder ,then with regard to incidence when generating total reflection between the boundary surface of film and base ,have deduced the phase defer from the theory. This is one of the rationales when incidence producing the phase defer only when total reflection happened on plating with the film type phase defer.Fourth chapter have selected and used two kinds of glass material, have applied second chapter's formula to have carried out design on material , have reached the structure angle that phase defer amounts stabilize most to given material. The implement has carried out treating fabrication on two Fresnel rhomb-type phase defer , has tested the varied relationship between incident light s wavelength and phase defer of rhomb that having not plated with the film.The Fresnel rhomb-type phase defer has been designed by the film-design-software , coated the rhomb in Korea Republic,ML_EB900 film machine , tested the result finally with testing apparatus self-putting up , the result indicates to the sample s designs that according with request.The originality-innovation-dot concentrates on fourth chapters mainly, design and error analysis to entire medium layer phase defer implement.