Diffraction gratings
What is a diffraction grating?
Diffraction grating is the optical element representing
periodic structure of grooves on flat, spherical or aspherical
surface of a substrate. Hologram diffraction gratings is
made with use of registration method of interference picture
by photosensitive material deposited on a substrate. On
a surface of a substrate the relief structure of grooves
with quasi-sinusoidal profile is formed after chemical processing
the photosensitive layer. For increase of diffraction efficiency
and power durability a metal coating is deposited on the
relief surface. HoloGrate, JSC at manufacturing of holographic
diffraction gratings uses unique inorganic photoresist of
own development. This photoresist possesses low light scattering
level and high resolution. The technology based on the use
of such photoresist allows to produce holographic diffraction
gratings with the various form and curvature of a surface.
HoloGrate, JSC manufactures the holographic
diffraction gratings of the following types:
- plane diffraction gratings;
- convex diffraction gratings;
- concave diffraction gratings (I-IV types) including
with aberration correction in flat field;
- diffraction gratings for laser including for laser
pulse compression;
- diffraction optical elements;
- grating scale for measurements.
Parameters of holographic
gratings:
The dimention :
- up to 200x400 for plane gratings;
- up to 200 mm Dia for concave gratings (I type) with
relative aperture up to 1:1 and for concave gratings (II-IV
types) with relative aperture upt to 1: 2,5.
Spectral range:
- from soft X-ray to 2 micromiters.
Groove frequency:
- From 100 groove/mm to 3600 groove/mm.
Diffraction efficiency:
- On the blazed wave length for polarized light >90%,
for non-polarized light >70%.
Relative intensity of light scattering:
- at 10 А ngstrom distance from spectrum line less
than 5x10-7
Resolution:
- grating resolution / its theoretical value ratio >0,9.
Gratings of HoloGrate,JSC are provided with various
reflective coatings:
- Al coating,
- Al + MgF 2 coating,
- Au coating;
- To increase beam stability of gratings dielectric multi-layer
combination are applied.
The basic advantages of our holographic diffraction
gratings:
- no ghosts in spectra,
- low scattering light and high signal/noise ratio,
- high resolution.
The basic field of application of holographic
diffraction gratings:
- spectral devices,
- for narrowing of spectrum line width in lasers,
- for laser pulse compression,
- for telecommunication systems,
- as scale grating for microscopes and other measuring
devices,
- for creation of original light illumination (laser
show and others).
Our holographic diffraction gratings are used in any spectral
devices of many institutes in Russia . Also our customers
are many companies from Russia , Belorussia , Lithuania ,
USA , United Kingdom , Italy , Netherlands , China
For more detailed information: grating@holograte.com
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