Abstract: A method and assembly for frequency stabilization of an optical signal especially from a laser, the assembly (11) comprising beam splitter (15), a passive frequency discriminator (16), and a pair of photodiodes (17 & 18). The beam splitter (15) in use receives a collimated optical beam (B) and diverts a sample beam (B1) which is directed towards the discriminator (16) which transmits a portion (B2) of said sample beam to one of the photodiodes (17) and reflects a second portion (B3) of said sample beam to the other photodiode (18). A control signal (S3) is derived from the respective intensities of the transmitted and reflected portions of the sample beam, and utilized to operate the electronic control to adjust the frequency of the laser output signal, if required, to maintain a specified frequency.

Abstract: A wavelength locker for locking the wavelength of a light beam substantially to a predetermined wavelength comprises at east one Fabry-Perot etalon arranged to receive a sample portion of the light beam and to produce at least one output light beam therefrom, the intensity of which is dependent upon the wavelength of the sample light beam, the Fabry-Perot etalon comprising diamond. Preferably the diamond etalon is a single crystal synthetic diamond having highly polished input and output faces without any reflective coatings.

Abstract: A method and assembly for frequency stabilisation of an optical signal especially from a laser, the assembly (11) comprising beam splitter (15), a passive frequency discriminator (16), and a pair of photodiodes (17 & 18). The beam splitter (15) in use receives a collimated optical beam (B) and diverts a sample beam (B1) which is directed towards the discriminator (16) which transmits a portion (B2) of said sample beam to one of the photodiodes (17) and reflects a second portion (B3) of said sample beam to the other photodiode (18). A control signal (S3) is derived from the respective intensities of the transmitted and reflected portions of the sample beam, and utilised to operate the electronic control to adjust the frequency of the laser output signal, if required, to maintain a specified frequency.

Abstract: A retail merchandising display system includes reconfigurable components which may be assembled to form perimeter wall fixtures, standing fixtures, tiered tables fixtures, etc. A set of basic components is provided which can be assembled into the fixtures, and disassembled to create other fixtures. Each of the fixtures is preferably provided with cladding which can be used to convey a brand identity.

Abstract: The article, typically for use in man-made satellites, has high emissivity and low reflectance in the thermal infra-red wavebands between 6 and 30 microns, and also in the visible wavebands. The article is employed either to cover individual solar-cells, thereby protecting the cells from ionizing radiation and micro-meteoroids, and to protect the adhesive bonding the article to the solar cell from u-v light, or as a thermal control mirror to prevent heat build-up. The article has good emissivity in the thermal waveband regions, so the cell can be maintained at a relatively low temperature.