Abstract:
A computer based system for testing an optical monitoring system includes a program having program instruction and optical monitoring system parameters, for implementing a plurality of tests of an optical monitoring system. A computer includes at least one processor for executing the program instructions, storage components for storing program instructions and test data, including the optical system parameters, a user input for inputting commands, and a display for displaying a menu of available test commands, test results and other data. An interface is provided for interfacing the optical monitoring system to tile computer for exchange of control and data signals. A fixture is provided for mounting the optical monitoring system during testing.
Abstract:
A light source (12) emits radiation which is maintained at a desired intensity by use of a photodetector which views the radiation and has a fixed relationship between incident radiation and output photodetector (18) current. Intensity of the radiation is established by varying electric current applied to the source, via a feedback loop (42, 24, 22, 34), to attain a reference value of the photodetector current, the photodetector current being representative of the desired value of radiation intensity. This procedure may be performed first in an air environment with a specific optical assembly of source and photodetector to establish the reference value of photodetector current for a desired value of radiation intensity. Thereupon, the optical system may be operated in a vacuum environment, and a monitoring of the photodetector current establishes the desired value of radiation intensity. Alternatively, the source is operated at a fixed value of excitation current, and an iris (44) or other radiation attenuator is operated to produce the reference value of photodetector current.
Abstract:
A flux containment device entraps an unneeded portion of the radiated ene emitted by a reference source lamp so that a determinable amount of radiation is projected to electro-optical sensors for calibration purposes. A double-walled, concentric can-shaped enclosure, provided with a nonreflective coating on its inside surfaces, has an aligned calibration optical axis aperture for projecting the determinable amount of radiation and a diametrically opposed light trap opening to accommodate a light trap that eliminates unwanted reflections. The double walls are held apart by nonconductive spacers to avoid unwanted heat transfer. A fan forces cooling air through an appropriately located vent hole in the can-shaped enclosure to avoid direct impingement on the lamp. One end of the can-shaped enclosure is provided with a disc-shaped baffle having appropriate spacing and openings to permit the flow of cooling air from the fan and the opposite end is appropriately shaped to accommodate a mounting surface, such as, for example, a lathe bed bench structure.
Abstract:
A source of illumination of constant color temperature and intensity including a lamp the color temperature of the light from which is dependent on the power applied to the lamp. There is a device for measuring the intensity of portions of the spectrum of the light and for providing signals indicative of those intensities. Means responsive to the signals adjust the power to achieve the selected color temperature. A light modulator adjusts the intensity without affecting color temperature. There is a spherical mirror centered on the lamp and the modulator is located between the lamp and the mirror and controls the brightness of the image of the lamp formed on the lamp by the spherical mirror.
Abstract:
A photometrical apparatus has a first light receiving element, and a second light receiving element less sensitive to temperature and other environmental influences than said first light receiving element whereby a value Pm of measured quantity of light from the subject is calculated from the following formula ##EQU1## Pr designates a quantity of light from a standard light source, Dr and Dm designate outputs of the first light receiving element generated by the light from the standard light source and the subject, Dpo and Dpt designate outputs of the first light receiving element generated by the light from the reference light source and the subject, and Dso and Dst designate outputs of the second light receiving element generated by the light from the reference light source and the subject.
Abstract:
In a spectrophotometer a light beam consecutively passes through a monochromator, a sample and standard light channel mirrorswitch; the spectrometer includes a device for focusing an image of the monochromator exit slit on the sample and standard. The device for focusing an image of the monochromatic slit is made in the form of a mirror objective common to the sample and standard light channels. The mirror objective comprises a convex mirror and a concave mirror, and, the convex mirror is being provided with a device for imparting periodic oscillations thereto and acting as a switching mirror element, thereby making a collimated beam alternately incident on a sample and a standard reference element. A photo sensitive device is provided to measure the amount of light passing through the sample in comparison with the light passing through the standard reference element depending on their relative optical densities.
Abstract:
A photographic camera with electronic exposure control and an exposure time indicator. A time scale is arranged along the length of an elongated light source which provides light at uniform intensity and as a function of the brightness condition prevailing at the object to be photographed. The light intensity of the source is varied through a photosensitive element in the electronic exposure control unit. A light attenuating member in the form of a wedge-shaped element in front of the light source extends along the length of the timing scale and provides attenuation which varies continuously in a progressive manner from one end of the wedge-shaped element to the other. A glass member with interference layers and illuminated from an auxiliary light source, is arranged to provide more precise indicating results.