5. Standard Reflection Gratings 标准反射光栅
Rflection gratings are used in a variety of optical applications requiring spatial separation of light by wavelength. LightSmyth’s ultra-low scatter reflection gratings are fabricated using projection lithography and reactive-ion-etch of single-crystal-silicon substrates. Gratings may be coated by a variety of metallic and dielectric materials and optimized for your application using our highly accurate coating simulation software and state-of-the-art coating facility. Each grating is a master, not a replica, resulting in low-scatter and long lasting performance.
LightSmyth reflection gratings reduce scattered light up to 100X compared to conventional commercial replicated holographic gratings and mechanically ruled gratings.

Advantages:
Each grating is a high-performance master, no polymers used
Very low cost (lower than prices of replicated gratings)
Free of replication/ruling flaws; ultra-low scatter
Robust single crystal silicon substrate
Copper-like thermal conductivity
Bests Pyrex glass in minimizing thermal expansion

Applications:
Remote Optical Sensors and Spectroscopy
High power lasers
Spectral beam combining
Astronomy and Space exploration

产品列表：
Part Number Line Density Groove depth Size
(Lines/mm) (nm) (mm)
SLG-C72-1212A-Al 7200 50 12.5 × 12.5
SLG-C72-2525A-Al 7200 50 25 x 25
SLG-C36-1212A-Al 3600 240nm(s) 12.5 × 12.5
SLG-C24-2525A-Al 2400 300nm(s) 12.5 × 12.5
SLG-C18-2009A-Al 1800 660nm 20 x 9
SLG-C17.4-2209-Al 1740 TBD 22.1 x 9.1
SLG-C16.5-2912-Al 1650 TBD 29.1 x 12.1
SLG-C14.8-2410-Al 1480 TBD 24.1 x 10.1
SLG-C12-1212A-Al 1200 1µm 12.5 x 12.5
SLG-C12-2525A-Al 1200 1µm 25 x 25

Notes: 1 Second dimension corresponds to the groove length
2 The standard reflective coating is Aluminum. Aluminum + MgF2 protective layer, Aluminum + Al2O3 protective layer, and gold coatings are available as an option
3 The peak efficiency wavelength, λPE, indicates wavelength(s) of highest efficiency for a given polarization state (in parenthesis)
4 P-polarization: Incident electric field vector is perpendicular to grating lines.
S-polarization: incident electric field vector is perpendicular to grating lines
5 Values are given for Littrow mount.
6 Typical grating thickness is approximately 0.7 mm.
Substrate height and width tolerance is +0.3 mm.
Grating composition: single crystal silicon, reactive ion etch, reflective metal coating.