Optical glass neutral density filters

Colored glass filters are optical components that control incident wavelength by distributing an optical absorbing substance in glass.

Longpass filters are ideal for a variety of applications, such as gas monitoring, temperature, sensing, thermal imaging and motion sensing, etc. Longpass filters block shorter wavelengths and transmit longer wavelengths. Blocking can be from reflectance, absorption or a combination. Transmission in the pass band can be enhanced with an antireflection coating on the second surface.

A band pass filter is a device that passes frequencies within a certain range and rejects (attenuates) frequencies outside that range, and it’s used to selectively transmit a portion of the spectrum while rejecting all other wavelengths.

IPL Filter is the key optical element for IPL (intense Pulsed Light) machine, which blocks the UV wave and transmits the useful wave from 400nm to 1200nm for laser equipment, such as photo-rejuvenation hair removal, vascular and acne treatment, skin rejuvenation.

Non-Polarizing Cube Beamsplitters also called NPBS Cube is a more sophisticated type consisting of two right- angle prisms cemented together at their hypotenuse faces.The cemented face of one prism is coated. Before cementing, with a metallic or dielectric layer having the desired reflecting properties, both in the percentage of reflection and the desired color. The absorption loss to the coating is minimal and transmission and reflection could be designed to 10%, 20%, 30%, 40%, 50%, etc.

Cr4+:YAG (Y3Al5O12) crystal is ideal for passive Q-switch operation of Nd:YAG and other Nd3+ or Yb3+ doped laser crystals in the wavelength range of 900 nm to 1200 nm. Passive Q-switches or saturable absorbers provide high power laser pulses without electro-optic Q-switches, thereby reducing the package size and eliminating a high voltage power supply. A remarkable feature of Cr4+:YAG is the high damage threshold of >10 J/cm2@1064 nm, 10 ns. Its absorption band extends from 900 nm to 1200 nm and peaks around 1060 nm with a very large absorption cross-section.

Diffusion bonded crystals consist of one laser crystal and one or two undoped material. They are combined by optical contact method and further bonded under high temperature. Diffusion Bonded Crystal helps to decrease thermal lens effect considerably of laser crystals, provides integral components to make compact lasers. HGO are able to supply various standard assembly and special customized bonding crystals.These diffusion bonded composite crystals have different wedge structures, Brewster angles, etc. It is used to effectively reduce the thermal effect of solid-state high-power lasers.

The Yttrium Orthovanadate (YVO4) is a positive uniaxial crystal grown with Czochralski method. It has good temperature stability and physical and mechanical properties. It is ideal for optical polarizing components because of its wide transparency range and large birefringence. It is an excellent synthetic substitute for Calcite (CaCO3) and Rutile (TiO2) crystals in many applications including fiber optic isolators and circulators, interleavers, beam displacers and other polarizing optics.