Determination of planeness and bending of optical flats

Abstract

The true contours, und istorted by gravitatio nal be nding, were determ ined for four 10 %-lIl ch-diameter stan dard optICal flats of fu sed quart z. The bending de fl ections of these flats \yere determined b~' a method base d upon the diffe rential be nd ing with thi c kn ess of t he flats. Bend ing deflect ion cu r ves of a fla t supported a' G t hree pOin ts equid istan t from the center o f the fla t and equ idistan t from each other were obt aine d. The locus o f the belld ing deflections at the center of a flat, s imilar!.v supported but with s upports at differe nt di, tances from the center , approx im ates a s traigh t line. This paper describes t he m ethod used to obtain the true conto ur'S and t he be nding de flection cu rves of the fla ts, and compares t he bending \'alues so determi ne d with t heo ret ically derived valLws.

Viscosity of fused silica and thermal noise from the standard linear solid model

“…We can get an estimate for U 0 from stationary consideration that obviously coincides with the common one [19,20]:…”

Validation of absolute planarity reference plates with a liquid mirror

“…The symbols we use, and their values, are listed in table 2. Following classical treatments [26][27][28][29][30], the shape of the plate is given by…”

Polarization phase-shifting Newton interferometer without errors caused by polarization crosstalk

“…They are immune to environmental perturbations and can be used with a low-coherence light source, they are therefore widely employed in optical applications such as flatness measurements [4,5], plane optical surface measurements [3,[5][6][7], and lens testing [3,8]. To heighten the measurement resolution of Newton interferometers, digital image processing [9][10][11][12][13] and polarization phase-shifting technique [14] have been proposed.…”