Build to Order Plane Ruled Diffraction Gratings



For these plane ruled diffraction gratings, the groove spacing and blaze angle determine the distribution of energy. The blaze direction for most gratings is specified for first order Littrow use. In Littrow use, light is diffracted from the grating back toward the source. Gratings used in the Littrow configuration have the advantage of maximum efficiency, or blaze, at specific wavelengths.

  • Ruled for high efficiency at design wavelength and blaze angle
  • Extensive selection of groove frequencies ranging from 1.9 to 5880 g/mm
  • Build to order from 100s of master gratings
  • Special size, substrate and coating options


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View Standard In-stock Plane Ruled Gratings

Master Grating Options

Plane ruled gratings are listed in order of groove frequency, with the lowest blaze angle listed first. Blaze wavelengths listed are for the first-order Littrow configuration. The maximum ruled area is groove length x ruled width. Click on a Master Grating Code (last 4 digits of a grating's part number) below to view master grating efficiency curves. Use the request a quote to get a quote based on your requirements. For additional diffraction grating options and custom capabilities, please see the Features section.

Features

Plane Ruled Diffraction Grating Construction

In general, for ruled diffraction gratings the groove spacing determines the diffraction angles, and the groove depth and blaze angle determines how diffracted energy is distributed between diffraction orders. Designed for first order Littrow use, Newport’s Plane Ruled Reflection Gratings are blazed to achieve extremely high single-order diffraction efficiency at particular design wavelengths. At Newport, we have three ruling engines in full-time operation, each producing high-quality master gratings each year. These ruling engines provide gratings with triangular groove profiles, very low Rowland ghosts, and high resolving power. Mechanically ruled, individual grooves are burnished with a diamond tool against a thin coating of evaporated metal. Utilizing a high fidelity cast replication process, developed and enhanced through years of research and manufacturing experience, we have the ability to provide duplicates of master gratings that equal the quality and performance of the master grating.

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Optimum Diffraction Grating Orientation

Plane Ruled Diffraction Gratings are most efficient when used near the design wavelength in the Littrow configuration, that is aligned so that the diffraction angle of the dominant diffraction order is coincident with the input beam, effectively behaving as a retroreflector at a specific wavelength. For blazed gratings, maximum efficiency occurs for wavelengths that the Littrow condition at the angle normal to the blazed grating facets. As ruled blaze gratings are asymmetric, correct orientation is indicated with an arrow marking on the size of the substrate. The arrow is on the side of the substrate perpendicular to the ruled grooves, and points toward the steeper edge of the triangular groove profile. Equivalently, the arrow points away from the grating normal toward the facet normal. The arrow should point toward the incident (and diffracted) beam.

Catalog Part Number System

All standard Richardson gratings have a part number according to the following format:

AA BBB CC DD - EEE x

  • AA indicates the type of grating (e.g., diced, plano, grism).
  • BBB indicates the size of the grating substrate.
  • CC indicates the substrate material
  • DD indicates the type of coating
  • EEE indicates the master grating groove parameters
  • x indicates the master grating type (e.g., ruled, holographic, echelle)

Please see Diffraction Grating Part Number System for additional information.

Grating Size Options

Grating size is usually dictated by the desired throughput, which is a function of the source and detector characteristics, the resolution of the optical system, and the required data-acquisition rate. The ruled area of each plane grating is shown in the specification table as the "Maximum Ruled Area" which is the groove length followed by the ruled width (for example, 65 x 75 mm indicates a groove length of 65 mm and a ruled width of 75 mm). This determines the largest size allowed from the size options table below.

The dimensions of the ruled area and the substrate may be altered from the regular catalog sizes at an additional cost. Special elongated grating shapes are available (e.g., for echelles and laser tuning gratings).

Size Code BBB Substrate Dimensions (mm) Ruled Area (mm)
108 16.5 x 58 x 10 12 x 52
004 30 x 30 x 10 26 x 26
066 28.5 x 58 x 10 23 x 52
107 40 x 40 x 10 36 x 36
060 25 x 100 x 16 20 x 96
067 50 x 50 x 10 46 x 46
022 30 x 110 x 16 26 x 102
006 58 x 58 x 10 52 x 52
009 68.6 x 68.6 x 9.1 64 x 64
119 68 x 68 x 6 64 x 64
114 50 x 100 x 16 46 x 96
033 76 x 76 x 16 70 x 70
010 76 x 85 x 16 70 x 79
013 90 x 90 x 16 84 x 84
015 110 x 110 x 16 102 x 102
017 110 x 135 x 25 102 x 128
020 135 x 165 x 30 128 x 154
025 110 x 220 x 30 102 x 204
027 135 x 220 x 35 128 x 204
028 165 x 220 x 35 154 x 206

Grating Substrate Material Options

The standard substrate material for small and medium-sized gratings is specially annealed borosilicate crown glass. Low expansion material can be supplied on request. Float glass may be used for small, diced gratings. In addition, replicas may be furnished on metal substrates, such as copper or aluminum, for applications with extreme thermal conditions. The substrate material codes CC are given below:

Substrate Material Code CC Substrate Material
AL Aluminum
BF Borosilicate float or equivalent
BK BK-7 glass or equivalent
CU Copper
FL Float glass
FS Fused silica or equivalent
LE Low-expansion glass
SP Special glass (unspecified)
TB BK-7, transmission grade
TF Fused silica, transmission grade
UL Corning ULE® glass
ZD Schott Zerodur®

Diffraction Grating Coating Options

All reflection gratings include a standard aluminum (Al) reflectance coating (Coating Code "01"). Gratings can also be replicated in gold (Au), or overcoated with magnesium fluoride (MgF2) or silver (Ag), to enhance reflectivity in certain spectral regions. The coating material codes DD are shown below:

Coating Code DD Coating Material Application
01 Aluminum (Al) General purpose applications.
02 Gold (Au) Offers higher reflectivity in the infrared.
03 Magnesium Fluoride (MgF2) Used to prevent oxidation of aluminum (Al) coatings, which helps maintain high reflectivity in the ultraviolet over time.
06 Protected Silver (Ag) Offers higher reflectivity in the visible and near infrared. Silver is protected from tarnishing by a dielectric coating, which helps maintain reflection over time.

Custom Diffraction Gratings

Newport is pleased to discuss special and unusual applications that are not addressed by our build to order catalog diffraction gratings. In some instances, none of the hundreds of master gratings we have in stock meet specifications, so a new master may be required. Please see Custom Diffraction Gratings for additional information on our capabilities.

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