Abstract:
A method of measuring light levels, particularly the measurement of exterior light levels in the zone of approach to a tunnel in which vehicles are moving, and from which exterior light levels the minimum light level to be programed inside the tunnel can be calculated, by means of a photo-sensitive cell installed in a recessed tube in order to sense light levels contained within a cone defined by the center of the cell, which constitutes the apex of the cone, and by at least the open end of the tube. The method includes limiting the quantity of light rays entering into tube via the cone, and a device is provided for implementing the method.
Abstract:
A radiation detector, including, a photodiode, has improved uniformity of sensitivity over the field of view because the receiving surface is provided by an optical diffusing layer, and the field of view is defined by a baffle arrangement, each internal surface of whichy is reflective. The baffle arrangement also defines a volume and the diffusing layer conforms to a part of the volume adjacent to the apex thereof. The diffusing layer may be provided by material, initially in liquid form, solidified in situ within the baffle arrangement. The receiving surface may be provided within a receiving head of the detector, spaced from the photodiode. Radiation may be transmitted from the receiving surface, whether part of a separate receiving head or not, to the photodiode by an optical fibre. An assembly of four consituent detectors, each having three orthogonally arranged mirrors, may together define a hemispherically shaped volume.
Abstract:
A multichannel optical sensing device is disclosed, for measuring the outr sky luminance or illuminance or the luminance or illuminance distribution in a room, comprising a plurality of light receptors, an optical shutter matrix including a plurality of liquid crystal optical shutter elements operable by electrical control signals between light transmitting and light stopping conditions, fiber optic elements connected between the receptors and the shutter elements, a microprocessor based programmable control unit for selectively supplying control signals to the optical shutter elements in a programmable sequence, a photodetector including an optical integrating spherical chamber having an input port for receiving the light from the shutter matrix and at least one detector element in the spherical chamber for producing output signals corresponding to the light, and output units for utilizing the output signals including a storage unit having a control connection to the microprocessor based programmable control unit for storing the output signals under the sequence control of the programmable control unit.
Abstract:
An evaluation circuit for use with electronic system which utilizes a plurality of individual transmitters of light, a like plurality of individual receivers of light, and a like plurality of light conducting paths. Each transmitter is connected to its corresponding receiver by a corresponding path so that the light emitted by any transmitter can only impinge upon the corresponding receiver. The light emitted is in the form of pulses. The transmitters are selectively actuated and deactuated in selected format by a multiplexer. The corresponding receivers are synchronized to respond in the same format by a demultiplexer whereby when the system functions properly each receiver will receive and respond only to the light pulse emitted by the corresponding transmitter. In the circuit, a measuring operation is initiated in which each transmitter-receiver pair is individually actuated in a selected sequence. A first channel produces a first signal when each receiver has properly received a light pulse emitted by its corresponding transmitter, the first signal suddenly changing value whenever a receiver fails to receive a light pulse emitted by its corresponding transmitter.
Abstract:
The invention relates to a selective detector arrangement for the detecting of approximately point-like collected light in a predetermined wavelength region and angle of the field of vision, with an optical collector system which is made from a material passing the light at a predetermined wavelength range and with a light sensitive sensor element. The essence of the invention resides in that within a predetermined wavelength range for the optical collector system there is a characteristic focal point surface, which is spaced from the focal point surfaces characteristic of wavelengths lying outside of such range and that the sensor element is coupled with the optical collector system in optical fashion over an aperture which is formed in the focal point surface associated with the predetermined wavelength range, and wherein the size of the aperture substantially corresponds in size to the size of the focal point surface of the light falling at the predetermined angle of the field of vision and in the predetermined wavelength range.
Abstract:
The color of a substantially spherical surface, such as that of a fruit, is measured by rotating the object about a vertical axis and projecting on the surface of the object, downwardly at 45*, an area of light that extends from the zenith to the equator of the object and is generally spherical triangular in shape, but differs from a spherical triangle in that the arc length s of the circles of latitude falling between the boundaries of the illuminated area is related as follows to the arc length s0 of the 45* circle of latitude:
Abstract translation:基本上球形表面的颜色,例如水果的颜色,是通过围绕垂直轴线旋转物体并在物体表面上向下45度向下测量从天顶延伸到 对象的赤道,并且通常为球形三角形,但与球面三角形不同,因为落在照明区域的边界之间的纬度圆的圆弧长度s与45的弧长s 0相关 纬度的DEG圈:s(x)= s0(1 + tan x)具有适当标志的X是45°角与通过照明表面穿过的圆环的中心角之间的差异。 为了测量颜色分布,使用相同的装置,但是只有一个足够小的区域被照亮以被认为是平面的,并且所选择的区域被手动地旋转到光点的下面。