Abstract:
A reflecting assembly for polarized white light includes at least one mirror associated with a birefringent compensator preventing the reflected light from having a large phase anisotropy. The mirror or mirrors are metallic and covered with a protective silica layer having a geometric thickness of from 0 to about 400A. The birefringent compensator is a crystalline plate of predetermined thickness depending upon the thickness of the protective layer. Known compensators may be used in place of the birefringent plate.
Abstract:
A variable feed mixer which includes two semi-reflective blocks for location in front of a television camera lens focussed for infinity and defining three injection apertures for receiving images from three sources, a variable focal length lens of the zoom type generally comprising a primary lens associated with the varying element, the primary lens having been removed being positioned in front of one of the injection apertures.
Abstract:
An apparatus for providing electrical signals representative of relative movement between two members includes a source of radiant energy conveniently light. A movement sensor fixed to one of the movable members comprises at least one detector responsive to energy from the source. A graduated track fixed to the other movable member is composed of a regular alternating series of marks and spaces capable of varying differently the energy from the source which is received by the detector by way of the track. Thus each detector provides a periodic undulating signal as the two members move relatively to one another. The or each signal is transformed by a reshaping device in which it is compared with a reference signal derived from at least one other detector exposed to energy from the source to derive a rectangular signal varying between one and the other of two logic levels. The reference signal may be derived by combining signals from two or more detectors exposed to energy from the source after modification by the track.
Abstract:
A REFRACTOMETER IN WHICH THE POSITION OF THE CHANGE IN INTENSITY OF THE REFRACTOMETER BEAM AT THE CRITICAL ANGLE IS SENSED BY A PHOTOELECTRIC SENSOR COMPRISING AN OPAQUE SCREEN DEFINING TWO OR THREE SLITS BEHIND EACH OF WHICH A PHOTOELECTRIC CELL IS POSITIONED, THE OUTPUTS OF THE CELLS BEING SUPPLIED TO AN ELECTRONIC CIRCUIT WHICH PROVIDES A SIGNAL AT THE MEANS POSITION OF THE CHANGE IN INTENSITY.
Abstract:
AN AUTOMATIC CAMERA DIAPHRAGM CONTROL USES A PHOTO RESISTANT CELL WHICH RECEIVES LIGHT THROUGH THE DIAPHRAGM. THE CELL IS SUPPLIED WITH AN ADJUSTABLE CONSTANT CURRENT. AN OVERALL SENSITIVITY RESULTS WHICH IS INDEPENDENT OF NOMINAL ILLUMINATION AND WHICH DEPENDS SOLELY ON THE RELATIVE VARIATIONS OF ILLUMINATION.
Abstract:
A device for mounting in or incorporation in a microscope apparatus for examining the walls of orifices of small size, the device including a plurality of mirrors carried on a mount and inclined relative to a common axis toward which they face, the mirrors diverging from that axis in the direction of the apparatus and away from the orifice to be examined.
Abstract:
There is described an apparatus for producing an electrical signal related to the varying concentration of a solution, for example a sugar solution. Light is inclinedly directed upon a surface of a prism which is in contact with the solution, so that light falling on one side of a boundary line, the position of which is a function of the concentration of the solution, is transmitted into the solution while light falling on the other side of this boundary line is totally reflected. The reflected light is directed towards an assembly including two photocells which are spaced apart in the direction of movement of the boundary as the solution concentration varies. The outputs of the two photocells are combined in a difference amplifier to yield a signal denoting that the solution concentration has reached a predetermined value dependent upon the position in said direction of movement to which the assembly is adjusted.
Abstract:
Mounting for a zoom lens having a fixed tube and an inner movable member, in which the fixed tube is provided with internal segments which hold a fixed lens, and the movable member is formed of longitudinal elements which extend between one on each side of the segments and terminate in opposed annular portions which locate the movable lenses.