Esco Optics, Inc.

Optical Flats, Single Precision Surface

Optical Flats, Single Precision Surface - Main image
$74.15 $117.7 In stock

Category: Optical Flats

Optical Flats are most commonly used as test plates to evaluate the accuracy of unknown optical surfaces. Esco manufactures optical flats out of G1 grade fused quartz; the low thermal expansion, abrasion resistance and general stability of this material allows continuous use with minimal degradation over time.

Esco offers optical flats with either one or two precision surfaces. Customers can test flat optical surfaces by holding the precision of an optical flat against the test surface. When placed under a monochromatic light, a fringe pattern can be seen through the back surface of the flat. This pattern describes the contour of the test surface, and is not affected by the accuracy of the rear surface.

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Customer Reviews (5.0 / 5 · 5 reviews)

Ella D. ★★★★★

I’ve been using this flat to check some lenses I’m polishing, and the low thermal expansion of the fused quartz is a huge plus for consistent results. The surface is remarkably smooth—no visible scratches or haze right out of the box.

Evelyn O. ★★★★★

The fused quartz construction gives me real peace of mind during long measurement sessions, since thermal drift is barely a factor. These flats are dead flat as far as my interferometer can tell, which is exactly what I needed as a reference for calibrating my other optics.

Leo V. ★★★★★

I've been checking surface figure on some vintage lenses and this flat gives me clean, readable fringes every time. The fused quartz barely moves with temperature swings in my shop, which matters when I'm chasing a quarter-wave.