Abstract: In a self-referencing instrument for measuring electromagnetic radiation, a mounting member to which a sample can be coupled moves the sample such that, in a first position, the electromagnetic radiation impinges on the sample, and, in a second position, the electromagnetic radiation does not impinge on the sample. A detection unit receives the electromagnetic radiation from the sample and generates a sample signal when the sample is in the first position, and the detection unit receives the electromagnetic radiation from the source and generates a reference signal when the sample is in the second position. A processor coupled to the detection unit processes the reference signal and the sample signal. This results in a continuous, accurate reference measurement, and permits the instrument to efficiently compensate for error, while offering accurate measurements.

Abstract: An improved procedure for manufacture of optical replication products comprising the use of a thin amorphous coating of carbon as a protective coating which also facilitates release during replication, between master and replication members. Particular attention is given to controlling the compressive forces of the carbon layer to provide good mechanical coatings on suitable optical surfaces. Thereafter, the replicated members may themselves be coated with the carbon as a protective coating only or for further use as a release-promoting "submasters".

Abstract: Indicia are formed in the surface of an ophthalmic contact lens by sublimating lens material with a high intensity beam of radiation. A beam of light from a laser is directed through one or more cooperating masks having openings defining desired indicia. The light which passes through the masks is directed upon a surface of a contact lens, advantageously near the periphery thereof. By selecting a proper wavelength and controlling the amount of energy directed upon the lens surface the depth of sublimation of lens material can be controlled. In this manner symbols can be formed upon the lens for uniquely identifying it.