Del Mar Photonics - Newsletter Winter 2010 - Newsletter April 2011

ZnSe cylindrical lenses - request a quote

Del Mar Photonics' ZnSe cylindrical lenses are used to focus or expand laser beams for applications such as infrared imaging, hyper-spectral imaging, optical metrology, laser scanning, spectroscopy, thermal cameras and laser diode systems.

CO2 cylindrical lenses can be used to focus a laser beam into a thin line or expand the output of a laser diode into a symmetrical beam in one axis only. They are available in 1 inch and 2 inch dia. sizes with 0.005 inch CT and feature focal lengths from 5 to 30 inches with 0.5% tolerance.

Offered with A/R coatings that typically provide 0.5% max. reflectance per surface at 10.6 micron and normal AOI, these cylindrical lenses have a 60-40 scratch-dig surface finish and 1 fringe surface accuracy at 633 nm. Centration error on these ZnSe lenses is 5 Arc-mins. max.


Zinc Selenide - ZnSe
 Model   Product Name+   Buy Now 
 PH-ZnSe-25.4-12.7   ZnSe hemicylindrical prism, 25.4 mm  Buy Now 
 R-ZnSe-25.4-25.4   ZnSe rhomb, 25.4x25.4 mm  Buy Now 
 RAP-ZnSe-12.7-25.4   ZnSe right angle prism, 12.7 x 25.4 mm  Buy Now 
 S-ZnSe-10-10-0.5   ZnSe slide, 10x10x0.5 mm  Buy Now 
 WS-ZnSe-100-100-10   ZnSe square window, 100x100x10, coated  Buy Now 
 VP-ZnSe-45-3-2 3/4   ZnSe viewport, 2-3/4  Buy Now 
 VP-ZnSe-73-4-4 1/2   ZnSe viewport, 4 1/2  Buy Now 
 W-ZnSe-1.5"-2.5"-1/4   ZnSe window, 38.1x63x6.35 mm, coated  Buy Now 
 W-ZnSe-105-6-AR   ZnSe window, ø 105 mm, thickness 6 mm, coated  Buy Now 
 W-ZnSe-12.7-1   ZnSe window, ø 12.7 mm, thickness 1 mm  Buy Now 
 W-ZnSe-20-3   ZnSe window, ø 20, thickness 3 mm  Buy Now 
 W-ZnSe-25-2-AR   ZnSe window, ø 25, thickness 2 mm, coated  Buy Now 
 W-ZnSe-25.4-2-AR-3-1   ZnSe window, ø 25.4 mm, thickness 2 mm, AR coated 3-12 m  Buy Now 
 W-ZnSe-25.4-3   ZnSe window, ø 25.4 mm, thickness 3 mm  Buy Now 
 W-ZnSe-60-3-K   ZnSe window, ø 60 mm, thickness 3 mm, coated  Buy Now 
 W-ZnSe-76.2-3-K   ZnSe window, ø 76.2 mm, thickness 3 mm, coated  Buy Now 

Application notes on ZnSe slides (under construction)

The fullerenes of C60 and C70 were deposited onto a zinc selenide slide

Microarray printing of bacteria on zinc selenide slides.
The microarray of microcolonies were stamped on a ZnSe slide after a 23 h incubation period.

Accelerating Bacterial Identification by Infrared Spectroscopy on ZnSe slide.
Infrared data analysis of the acquired FTIR spectra.

Cryocondensation step on a ZnSe-slide.
The ZnSe slide itself is cooled via connection to a liquid nitrogen container.

Enzyme-catalyzed modifications of macromolecules.
These macromolecules are reactive either as cryogenically milled powder suspended in the organic solvent or as a thin film deposited onto ZnSe slides.

GC/FT-IR spectra of 8.6 ppm of t-butyl benzene deposited on a ZnSe slide.
The lower spectrum was measured on the bare ZnSe slide.

Synchrotron FT-IR microspectroscopic analysis of necrotic bone.
Sections were fixed on ZnSe slides, suitable for infrared transmission analysis.
Sections were cut from each case; one was placed on ZnSe slide.

Zinc Selenide (ZnSe) Components

Zinc Selenide (ZnSe) is the most popular material for infrared application. Due to very wide transmission range covering 0.6 to 20 m m CVD grown ZnSe high optical quality material is used to manufacture optical components (windows, mirrors, lenses etc.) for high power IR lasers.

Physical Properties

Crystal type cubic
Lattice constant       a=5.657Е
Density 5.27 g/cm3 at 25 C
Melting point 1525 C
Refractive index 2.417 - 2.385 @ 8 - 13 m m
2.40272 at 10.6 m m
Transmission band 0.6 to 20 m m
Bulk absorption coefficient 5 ґ 10-4 cm-1 @ 10.6 m m
Young's Modulus 6.72 ґ 109 dynes/mm2
Specific Heat at 25 C 0.085 ca/g C
Linear thermal expansion 7.57 ґ 10-6 / C at 20 C

General Specifications of Zinc Selenide Optical Components

Material ZnSe
Surface Quality 40-20 scratch & dig
Clear aperture 90% of diameter
Diameter tolerance +0.0, -0.1 mm
Thickness tolerance +0.1, -0.25 mm
Surface Irregularity l /2 per inch @ 633 nm over clear aperture
Coatings Typical available coatings for ZnSe include BBAR for 0.8 to 2.5m, 3 to 5m, 1 to 5m, 8 to 12m, and the 3 to 12m spectral regions and single wavelength AR coating  at 10.6m RЈ 0.5% per surface. Many other specialized wavelength bands are possible within the 0.6 to 16m range.


Standard ZnSe windows (uncoated) 

Diameter, mm

Thickness, mm


12.5 (or 0.5")



25.0 (or 1")



40.0 (or 1.5")



50.0 (or 2")




Zinc Selenide custom made windows, lenses, Brewster windows, mirrors, beamsplitters and other components are available on request.

Zinc selenide most obvious and important advantage over other materials is its low absorption in the red end of the visible spectrum. This allows the ubiquitous helium neon laser to be used as a convenient and inexpensive alignment or sighting tool for infrared laser beams. Prealignment of optics may be necessary merely because the infrared beam is invisible to the eye, or in addition because the infrared laser beam is of such a high energy misdirected laser beam can be extremely dangerous to equipment or personnel.

Although zinc selenide has this clear advantage over silicon and germanium, unfortunately it is not an easy material from which to produce optics. Firstly, it is not a naturally occurring material and has to be synthesized using a difficult process (CVD). Secondly, the dust, which is generated when zinc selenide is ground and polished constitutes a significant health hazard as a cumulative toxin. Also, it is not a particularly hard substance and scratches easily.

Refractive Index

Wavelength, m















Refractive Index

















Although the internal transmittance of zinc selenide is very high (absorption <= 0.0005cm-1 at 10.6mm), the relatively high refractive index (2.4 at 10.6m m) cause reflection losses of nearly 30%. Unless such losses can be tolerated, zinc selenide optics should always be antireflection coated. Because of the high refractive index, single and double layer antireflection coatings can be very effective.

Zinc selenide is not hygroscopic unlike certain salts which are used for windows in the infrared.


Del Mar Photonics featured optical components

Del Mar Photonics continuously expands its optical components portfolio. Browse our online store, read monthly notes about our featured optical products or just send us your requirements or product ideas

Axicon Lens
Axicon lens also known as conical lens or rotationally symmetric prism is widely used in different scientific research and application. Axicon can be used to convert a parallel laser beam into a ring, to create a non diffractive Bessel beam or to focus a parallel beam into long focus depth.
Del Mar Photonics supplies axicons with cone angles range from 130 to 179.5 for use with virtually any laser radiation. We manufacture and supply axicons made from BK7 glass, fused silica and other materials.
buy online - download brochure
Del Mar Photonics offers optical elements made of high quality synthetically grown Rutile Titanium Dioxide crystals. Rutile (TiO2) coupling prisms
Del Mar Photonics offers optical elements made of high quality synthetically grown Rutile Titanium Dioxide crystals. Rutiles strong birefringency, wide transmission range and good mechanical properties make it suitable for fabrication of polarizing cubes, prisms and optical isolators. Boules having high optical transmission and homogeneity are grown by proprietary method. Typical boules have 10 - 15 mm in dia. and up to 25 mm length. Optical elements sizes - from 2 x 2 x 1 mm to 12.7 x 12.7 x 12.7 mm. Laser grade polish quality is available for finished elements. So far we the largest elements that we manufactured are 12 x15 x 5 mm, in which optical axis is parallel to 15 mm edge, 5 mm is along beam path, 12 x 15 mm faces polished 20/10 S/D, one wave flatness, parallelism < 3 arc.min. (better specs. available on request).
more details - buy online - download brochure

Vacuum viewport

Del Mar Photonics offer a range of competitively priced UHV viewports , Conflat, ISO or KF including a variety of coatings to enhance performance. Del Mar Photonics viewports are manufactured using advanced techniques for control of special and critical processes, including 100 percent helium leak testing and x-ray measurements for metallization control. Windows Materials include: Fused silica, Quartz , Sapphire , MgF2, BaF2, CaF2, ZnSe, ZnS, Ge, Si, Pyrex. Standard Viewing diameters from .55" to 1.94 ".
Coating - a range of custom coatings can applied - which include
- Single QWOT
- Broad Band AR
- V coatings
- DLC (Diamond like coating)
more details - request a quote

Manufacturing challenging optical components

Our group works to characterize the interaction of biomolecules with solid surfaces, writes Dennis Hore of University of Victoria, Canada.  Nature designs proteins with well-defined structures in solution.  The conformation of these molecules may serve a structural purpose, or a chemical one in the case of enzymes.  In order to further the progress of technologies that immobilize such molecules on synthetic surfaces (like biosensors employing enzymes), it is important to have a detailed understanding and control of the interactions of these molecules with the surface more
For that project Del Mar has been able to manufacture all shapes of prisms from CaF2, fused silica, and ZnSe according to our custom specifications.

Del Mar Photonics online store features windows, prisms, lenses, attenuators, etalons, crystals and wafers, and other items. Axicons, barium fluoride windows, germanium etalons, rutile (TiO2) prisms, microchannel plates and detectors, saturable absorber mirrors, photoconductive THz antennas, lithium niobate wafers and crystals and many other high quality affordable components for scientific research and OEM production are delivered globally from stock.
Micro Prism from Del Mar Photonics
We are looking forward to hear from you and help you with your optical and crystal components requirements. Need time to think about it? Drop us a line and we'll send you beautiful Del Mar Photonics mug (or two) so you can have a tea party with your colleagues and discuss your potential needs 

Trestles LH femtosecond lasers with integrated DPSS DMPLH laser pump - DPSS DMPLH lasers