非偏振分光棱镜(NPBS)也称为NPBS立体分光镜，是一种更复杂的类型，由两个直角棱镜组成，它们在斜边面处被固定一起。一个棱镜的胶合面有镀膜，在胶合之前，镀有所需反射性能的金属介质膜，具有特定的反射百分比和颜色。镀膜吸收损耗最小，透过率与反射率可设为10%、20%、30%、40%、50%等。

偏振分光棱镜由两个直角棱镜胶合而成，其中一个棱镜的斜面镀有偏振介质膜。当与正常入射、非偏振光一起使用时，入射光被分成两束偏振光，P偏振光可直接穿过，S偏振光以90°角反射出来。

锥形透镜是圆柱形棒透镜，其一端加工成锥形表面。 通常研磨杆的圆周，而抛光锥形表面。

1.  Germanium (Ge)

Germanium (Ge) is the preferred lens and window material for high performance infrared imaging systems in the 8–12 μm wavelength band. Its high refractive index makes Ge ideal for low power imaging systems because of minimum surface curvature. Chromatic aberration is small, often eliminating the need for correction.

2. Silicon (Si) 

Silicon (Si) is grown by Czochralski pulling techniques (CZ) and contains some oxygen that causes an absorption band at 9 microns.To avoid this, material can be prepared by a Float-Zone (FZ) process. Optical silicon is generally lightly doped (5 to 40 ohm cm) for best transmission above 10 microns, and doping is usually boron (P-type) and phosphorus (N-type). After doping silicon has a further pass band: 30 to 100 microns which is effective only in very high resistivity uncompensated material.
 
CZ Silicon is commonly used as substrate material for infrared reflectors and windows in the 1.5-8 micron region. The strong absorption band at 9 microns makes it unsuitable for CO2 laser transmission applications, but it is frequently used for laser mirrors because of its high thermal conductivity and low density. Application as window, lens in the 1.5 - 8 um region; Mirror for CO2 laser and spectrometer applications.
 

ZnS MultiSpectral Under intense heat and pressure, defects within the crystalline lattice are virtually eliminated, leaving a water-clear material with minimal scatter and high transmission characteristics from 0.4 to 12 microns. This material is particularly well suited for high-performance common aperture systems that must perform across a broad wavelength spectrum.

Specifications:

Material: ZnS MultiSpectral
Diameter Tolerance: --------------------- +0.0, -0.1mm
Thickness Tolerance: -------------------- ±0.1mm
Clear Aperture: ---------------------------->85%
Parallelism: -----------------------------------3 arc minute
Surface Quality: ----------------------------80-50 scratch and dig
Wavefront Distortion: -------------------- λ /2 per 25mm @633mm
Bevel: -----------------------------------------Protective  (<0.2mm x 45° )
Coating: -------------------------------------- Optional （Uncoated, AR Coating, etc.）

4. ZnSe material

ZnSe is a preferred material for lenses, windows, output couplers and beam expanders for its low absorptivity at infrared wavelengths and its visible transmission. For high-power applications, it’s critical that the material bulk absorption and internal defect structure be carefully controlled, that minimum-damage polishing technology be employed, and the highest quality optical thin-film coatings are used. The material absorption is verified by CO2 laser vacuum calorimetry. Our quality assurance department provides testing and specific optics certification on request.

ZnSe is non-hygroscopic and chemically stable, unless treated with strong acids. It’s safe to use in most industrial field, and laboratory environments.