Fused Silica Optical Flats

Pricing for Stock Optical Flats

Single Surface, Round: One surface is polished to flatness indicated in table. Other surface has "commercial polish" which means it is clear but flatness is unspecified.

Size Round	Lambda/20 0.000001" ($US)	Lambda/10 0.000002" ($US)	Lambda/4 0.000004" ($US)	Thickness
1"	133	120	110	0.5"
2"	202	168	155	0.625"
3"	366	329	300	0.688"
4"	535	485	438	0.75"
5"	794	576	550	0.875"
6"	1125	900	795	1"
8"	2340	1845	1475	1.313"
10"	3475	3200	2900	1.688"
12"	5625	4950	4500	2"

Double Surface, Round: Both surfaces are polished to flatness indicated in table.

Size Round	Lambda/20 0.000001" ($US)	Lambda/10 0.000002" ($US)	Lambda/4 0.000004" ($US)	Thickness
1"	205	150	145	0.5"
2"	235	178	168	0.625"
3"	495	440	350	0.688"
4"	700	600	540	0.75"
5"	1080	810	740	0.875"
6"	1600	1350	1140	1"
8"	3240	2600	2100	1.313"
10"	4800	3250	3900	1.688"
12"	6650	5650	4950	2"

Most items are ready to ship within one week after receipt of order. Other sizes and shapes can be made. Call or e-mail us to request a quote.

Common Specifications

Material: Fused silica or fused quartz.
Tolerance of diameter and thickness: +/- 0.060 inches.
Typical surface roughness is 5 Angstroms RMS.
Flatness values are Peak-to-Valley where Lambda=633 nm.
Measurements are NIST certified..
Parallelism is typically 4 arc minutes or better, but it is not guaranteed.
Scratch-dig is typically 80-50, but it is not guaranteed.
Parallelism up to 1 arc second and scratch-dig to 10-5 and 5-0 are available. Contact us to request a quote.
Each optic is packed in its own storage case.
*Optional Coating: Contrast-enhancing TiO coating is available for the single-sided flats. If you would use an optical flat in contact testing and the part to be tested has a flat or matte finish, this coating may enhance the contrast of the fringe pattern, which would make the fringes easier to see. This coating does not make the surface more resistant to scratches.

The pricing in the tables above are for optical reference flats that are designed to be used in surface contact testing, or as front surface mirrors if appropriately coated. They are not designed to be used as high-precision windows, where you are using the light that transmits through the optic, not just reflects off one surface of it. Although they may work well as windows for some applications, parameters affecting their use as windows such as parallelism, internal defects and striae, and transmitted wavefront accuracy are generally of good quality, but they are not held to any specific value. If you are looking for high-precision windows where you need to hold the transmitted wavefront accuracy to a specific value, call or e-mail for a quote.