| Infrared optics is an important part of the infr ared ther mal imaging system. C urrently, materia ls whic h can be used to produce an infrared le ns inc luding monocrysta lline ger manium, ZnSe and chalcogenide glass etc. Among t hese, germa nium crystal mater ial is an expens ive semico nductor mater ials, as a crystalline mater ia l, germanium can only be produced and processed by us ing the costly single- point d ia mond tur ning processing techno logy, t his makes the product ion o f infrared optica l lens to be limited. C halcogenide glass has w ider range o f infrared transmiss io n(1~14μm), higher infrared light trans mittance, lower ther mal re fractive index coeffic ie nts and lower dispe rsion coeffic ient, so it is an exce llent materia l for the manufacture of infrared optica l le nses. Meanwhile, the chalcoge nide glass, compar ing to ger manium and ZnSe, has a low cost and can use glass mo ld ing process. This makes the process ing costs of c halc oge nide glass reduced, and the processing effic ie ncy of cha lcogenide glass improved. Therefore, cha lcogenide glass is the most promising material to replace the germanium and other infrared lens materials.This research used mo ld ing technolo gy in the processing o f cha lcogenide glass. Cons idering the fact that glass press mo lding machine is not mature yet in our countr y and is ver y expens ive to import fro m abroad. so, a set of an one- step GMP machine design pla ns is put forward in this d issertatio n to la y the foundatio n for the designing of glass press mo ld ing machine w hich be used for experiment and production. The main conclusions and contents of this dissertation are decalared below:(1) An one- step GMP machine is designed, and the working pr inc ip le of the machine is also introduced. The design of the machine cons ists of two parts : power transmiss io n device and heat ing part. Power transmiss io n device design inc lude : selectio n and verificat ion of ball screw, select ion of reducer, guide block select ion of slide guide, servo motor select ion and ver ificat ion. The design of the heat ing part inc ludes: the structure des ign of the heat ing block and the design of the heating system control principle.(2) The mold ing q ua lity o f a glass le ns is great ly influenced by t he heat ing unifor mit y of the glass lens whe n it is mo lded by g lass press mo ld ing mac hine. Therefore, a series of numer ica l simulat ion experiment is carried out by us ing the MSC.Marc to study the arrange ment of heat ing rod in heat ing plate of glass press mo ld ing machine. The simulated results show that the soak ing effect of heat ing plate is great ly influenced by the distance between heat ing rods, and when the distance between heating rods is set to 26 mm, the soaking effect of heating p late is the best that the temperature difference is controlled within 1℃.(3) Mould for mold ing cha lcogenide glass is designed, and the mo ld ing experiment of cha lcogenide glass is carried out by us ing this mould, and the qua lit y of the mo lded lens is good. This le ns is measured by Taylor Hopson PGI 1240. The result shows that the aspheric PV va lue of t he lens conve x sur face is 1.475μm. The aspher ic PV value of the lens concave surface is 1.475μm. |
PDF Full Text Request