Abstract: Concentration gradients in samples to be evaluated are detected by measuring the deflection of a probe light beam passed through the sample using the principals of Shlieren optics. Specific chemical compounds in a sample can be detected and identified by supplying excitation energy to the sample where such energy is selected to be absorbed by the chemical compound to be specifically identified and not by other compounds in the sample. The absorption of the excitation energy by the absorbing compound produces a temperature gradient within the sample which causes deflection of the probe light beam and signals representative of such deflection may be separated from signals representative of deflections caused by other refractive index gradients present in the sample. A light emitting diode may be used to generate the probe light beam.

Abstract: An atmospheric optical calibration system is provided to compare actual atmospheric optical conditions to standard atmospheric optical conditions on the basis of aerosol optical depth, relative air mass, and diffuse horizontal skylight to global horizontal photon flux ratio. An indicator can show the extent to which the actual conditions vary from standard conditions. Aerosol scattering and absorption properties, diffuse horizontal skylight to global horizontal photon flux ratio, and precipitable water vapor determined on a real-time basis for optical and pressure measurements are also used to generate a computer spectral model and for correcting actual performance response of a photovoltaic device to standard atmospheric optical condition response on a real-time basis as the device is being tested in actual outdoor conditions.

Abstract: A luminometer construction including means for supplying samples contained in respective cuvettes 20, in succession to be examined, the cuvettes being introduced into a carrier 10 having a cuvette gripper 19, the carrier 10 defining an examination chamber 21 into which the cuvettes are inserted, the carrier 10 being rotatable between a loading and a test position in which the examination chamber 21 is adjacent to a photo-multiplier device 25, whereby testing of a sample in a curvette 20 can be carried out, the examination chamber 21 having an edge in a plane inclined to the axis 11 of rotation of the carrier 10, and the photo-multiplier device 25 being arranged with its optical axis 26 perpendicular to such plane.

Abstract: A vertical beam spectrophotometer for measuring the light absorption of an assay prepared using standard wet chemistry procedures and conventional solid phase coated bead technology is disclosed. The spectrophotometer measures the absorption of the assay in a conventional reaction cuvette with the bead remaining in the cuvette. The light source of the spectrophotometer illuminates the bead, which diffuses the light into the surrounding assay solution. A lense projects the diffused light onto a photocell which converts it into an electrical signal having magnitude related to the light absorption of the assay. The signal is processed in a known manner by conventional processing circuitry to obtain an absorption value.

Abstract: A take-up strip is applied to the element to be investigated, (for example the skin or the hair of a living subject), for a given time and with a given pressure; the side of this strip intended to come into contact with the element to be investigated is matt; the quantity of light reflected by the matt side of the strip is measured before and after impregnation with the greasy product: the quantity of the greasy product located on the surface of the element investigated is derived from the reflection measurement. The detection means is constituted by a phototransistor whose output signal is processed by an analog/digital converter associated with a programmable computer; the strip is disposed on a displaceable support. The reflection reading all along the strip gives a brightness curve in accordance with the location on the strip. For the hair, this curve reflects the greasy aspect from the root to its tip.

Abstract: A method, and a device for practicing the method, for marking the configuration of a vehicle-mounted mirror which has initially been set to a desired perspective, thus enabling a single, unaided person within reach of a misaligned mirror to quickly and reliably readjust it to reproduce the previously marked perspective even though that desired perspective cannot be viewed from the adjuster's position.