Changchun Hengyi Optics CO., Ltd could supply kinds of Pass Filters such as Neutral Density Filters,Short/long wave Pass Filters.

 Short/long wave Pass Filters
(i)Visible Long wave Pass Filters
(ii)Visible Short Wave Pass Filters
(iii)NIR Long Wave Pass Filters
(iv)NIR Short Wave Pass Filters

Our company's Short and Long wave pass Filters exhibit a sharp transition from a spectral region of attenuation to one of transmission. these sharp-cut edge filters are distinguished by their high rate of transition between their region of reflection and transmission. This high rate of transition makes them an excellent choice as emission filters in fluorescence applications, and as order sorting filters in photometry. They are also very useful as stray light or trim filters, to eliminate any unwanted near band radiation.
 
Custom products
Our ability can be up to:
Material: BK7A or other meterials  Diameter: 2-300mm
Diameter Tolerance: -0.10mm
Minimal Thickness:0.5mm
Parallelism: 1-3 arc minutes
Flatness: λ/10 at632.8nm
Surface Quality:20-10 scratch dig
Blocking Range:Specified by customers
Transmission Range:Specified by customers
Clear Aperture: 90% of Diameter

Bandpass Filters
(i)Narrow Bandpass Filters
(ii)Long Bandpass Filters

A bandpass filter has a transmission band surrounded by two blocking bands that allow only a portion of the spectrum to pass. The characteristics of the bandpass are controlled by multilayer dielectric coatings. Blocking is usually achieved with a combination of color filter glass and specially designed metallic films. The bandpass and blocking elements are laminated (epoxied) together to form a single unit and then edge sealed to prevent degradation due to moisture.
 
Custom products
Our ability can be up to:
Material: Optical glass
Diameter: 2-300mm
Diameter Tolerance: -0.10mm
Minimal Thickness:0.5mm
Parallelism: 1-3 arc minutes
Flatness: λ/10 at632.8nm
Surface Quality:20-10 scratch dig
Center Wavelength:Specified by custome