The elastic-port immersion cell (10) is an optical oil immersion vessel which has a flexible latex (or other) sheath (24) protruding from its sidewall. The sheath is affixed to an opening in the wall of the vessel using a collar, O-ring (26) or other connecting means. The base of the vessel is an optical glass window. A sample (20) mounted on to the end of spindle (14) is placed into the cell. The end of the spindle (14), without the sample, is inserted into the sheath and the latex together wit...

A method of and an apparatus for forming a multi-layer film, includes: a thickness control device for controlling an optical film thickness or a thickness of each of the layers of the multi-layer film; a multi-layer film monitoring substrate on which the multi-layer film is formed; a measurement device for measuring the optical characteristics of the multi-layer film formed on the multi-layer film monitoring substrate; and a processing device which processes the results obtained by the measureme...

A method and apparatus for determining the size and shape to which a finished lens used to make an eyeglass lens is to be cut. Coordinates which define the outer perimeter of a lens are determined by illuminating either an eyeglass frame or a lens. An image of the shadow of the frame or lens is captured by an imaging device. A first linear polarizing filter is positioned optically between a light source and the membrane. A second linear polarizing filter, oriented at 180.degree. from the first f...

Longitudinal position of the end of a drill bit (21) is determined in order to accurately control depth of a hole to be drilled. A drill bit (21) is rotated at a predetermined speed and caused to penetrate a light beam of known vertical position. The light beam, which is generated by a light emitting diode (50) and received by a photo transistor (54), is modulated by the flutes at the tip of the rotating bit to cause the photo transistor to provide an output signal that is modulated at a frequen...

A hand-held apparatus and process for measuring the gap and mismatch of two adjacent surfaces. The apparatus includes two strobe lights positioned within a hand-held housing. An optical interface within the housing directs a portion of the light generated by each light source into substantially parallel planes which are projected out of the opening of the housing at converging angles onto the surfaces to be measured. A camera within the housing captures the resulting image and generates a signal...

A wet steam monitor determines steam particle size by using laser doppler velocimeter (LDV) device to produce backscatter light. The backscatter light signal is processed with a spectrum analyzer to produce a visibility waveform in the frequency domain. The visibility waveform includes a primary peak and a plurality of sidebands. The bandwidth of at least the primary frequency peak is correlated to particle size by either visually comparing the bandwidth to those of known particle sizes, or by d...

Planar light sources are directed at an article on either side of the optical axis so that the trace of each light beam defines a line, on either side of the optical axis, whose form is dependent on the shape of the surface of the article. To determine whether the article is in focus, the distance between the two lines is measured. To determine whether the article is in correct pitch, the distance between each line and the optical axis is measured and compared. To determine whether the article h...

A gap measurement device includes a first roller and a second roller. The first roller and the second roller define a gap which varies due to thermal expansion and contraction of the rollers. A first optical probe measures a first distance to the first roller and generates a first-distance signal indicative of the first distance. A second optical probe measures a second distance to the second roller and generates a second-distance signal indicative of the second distance. An electronics module g...

A lens meter including an illumination light source for illuminating a measurement target, a target projection optical system for projecting the measurement target onto an inspected lens, an observation optical system for observing a focused state of the projected target image and target moving device for moving the measurement target in an optical axis direction or the like to thereby measure a refracting power of the inspected lens on the basis of an amount in which the measurement target is m...

In an ellipsometer, a phase-modulated, polarized light beam is applied to a sample, electrical signals are obtained representing the orthogonal planes of polarization of the light after it has interacted with the sample and the constants of the sample are calculated from the two resulting electrical signals. The phase modulation is sufficiently small so that the calibration errors are negligible. For this purpose, the phase modulator phase modulates the light within a range of no more than ten d...