Abstract:
A single rotating mirror is combined with a plurality of fixed mirrors to provide an alternating optical path. The entrance and exit beams can be made quite narrow and are not varied as the device switches between two alternate equal-length internal paths. Such an alternator has application in optical measurement systems where it may be desired alternately to illuminate a pair of reference light absorption cells.
Abstract:
A beam from a light source is collimated and directed at right angles into the input face of a Koster''s prism. From the output face of the prism emerge a measuring and reference beams which are parallel to each other. Lenses across the latter beams focussing the respective beams in the plane of a chopper disc. Diaphragms are positioned between the lenses and the disc.
Abstract:
Radiation sensor including a detection assembly and a chopper assembly, which are mechanically coupled to delimit a main cavity; and wherein the chopper assembly includes: a suspended movable structure, which extends in the main cavity; and an actuation structure, which is electrically controllable to cause a change of position of the suspended movable structure. The detection unit includes a detection structure, which faces the main cavity and includes a number of detection devices. The suspended movable structure includes a first shield of conductive material, which shields the detection devices from the radiation, the shielding of the detection devices being a function of the position of the suspended movable structure.
Abstract:
The invention relates to a method and a device for obtaining a low-noise optical signal. According to the method, a luminous beam is injected through two apertures and after detection respectively a basic optical signal (21) and a corrective optical signal (22) are generated. Both optical signals obtained (21, 22) are subtracted, so that a resulting optical signal is generated, forming the low-noise optical signal. The apertures are preferably two slits of a spectroscope, the optical signals being expressible relative to the wavelength.
Abstract:
The present invention relates to an apparatus for determining the diffuse reflectivity of a sample surface of small dimensions, especially of the test field of a test strip for determining the substances contained in a body fluid. The apparatus has a semiconductor light emitter, especially a light-emitting diode, for the emission of visible or infrared light to the sample surface, a measuring receiver for receiving the light diffusely reflected by the sample surface and producing an electrical signal corresponding thereto, an evaluating means including an electronic circuit for converting the receiver signal to a value corresponding to the diffuse reflectivity, and a reference channel using the light from the same emitter for the calibration of the apparatus and for the elimination of errors of measurement caused by variations of the emitter or of other electronic components.