Abstract: The present invention relates to interferometers with adjustable path length differences (lags). The method of adjusting the interferometer lag is by selectively enabling a plurality of different fixed path length delay elements in either or both of the interferometer arms or paths. In addition, an interferometer with a small but continuously adjustable lag may be extended to much greater lags by adding such delay elements to one or both of the interferometer's paths.

Abstract: A polarization insensitive tunable optical filter system combines an interference filter or the like with a quarter wave plate and a retro-reflector. The retro-reflector is situated and aligned to intercept light reflected from the filter, and the quarter wave plate is disposed between the filter and the retro-reflector. Hence, the pass signal reflected off the filter a first time passes through the quarter wave plate a first time, reflects off of the retro-reflector, passes through the quarter wave plate a second time, and reflects off of the filter a second time.

Abstract: A 1×N optical switch according to the present invention switches between output fibers without the need for active alignment by utilizing two beam deflecting stages, for example first passing the input beam through a translating element and then through a beam angle adjusting element. The translating element directs the input beam toward the selected fiber, and the angle adjusting element directs the beam toward the core of the selected fiber.

Abstract: Apparatus and methods for switching an optical signal between a first path and a second path, where the switching occurs continuously such that substantially all of the optical signal passes through the first path or the second path during switching.

Abstract: A tunable interference add/drop filter system combines an interference filter or the like with a mirror attached adjacent to the filter at an angle under 180° to form a reflector assembly. The reflector assembly is rotated to tune the filter system. The dropped output passes through the filter, while the passed output reflects off of the filter and the mirror. The direction of the passed output beam is a fixed angle from the input beam, and the beam is translated sideways by a fixed amount, no matter how much the reflector assembly is rotated. Thus the dropped output (or complementary output) can be retained. A null state switch prevents light from reaching the filter while the filter system is tuning.

Abstract: An optical detection system is adapted particularly for detection of biological reactions, especially fluorescent or chemilluminescent reactions. An excitation source, preferably a laser, illuminates a portion of an object to be examined, the portion preferably comprising one microlocation out of an array of microlocations. An intervening optical detection platform serves to direct the excitation radiation, preferably through use of a scanning system, most preferably through use of an x-y mirror-based scanning system to the portion of the object to be illuminated. A detector, preferably a photomultiplier tube, receives the emitted radiation from the objects to be examined, the detector being characterized in that the diameter of the region examined by the detector is the same as or smaller than the diameter of the illuminated region, and comprises less than the entire surface of the object to be examined, and most preferably images a whole or a part of a single microlocation.

Abstract: An optical detection system is adapted for detection of biological reactions. An excitation source illuminates a portion of an object to be examined, the portion preferably comprising one microlocation out of an array of microlocations. An intervening optical detection platform serves to direct the excitation radiation to the portion of the object to be illuminated. A detector receives the emitted radiation from the object to be examined, the detector being characterized in that the diameter of the region examined by the detector is the same as or smaller than the diameter of the illuminated region, and comprises less than the entire surface of the object to be examined, and most preferably images a whole or a part of a single microlocation. In operation, a microscopy system is formed in which the excitation radiation is substantially in focus at the surface of the object to be examined.

Abstract: An optical inspection system which inspects for the presence of defects in colored labels placed, for example, on the side walls of cylindrical beverage cans. The optical inspection system utilizes a conveyor for conveying the beverage cans in a production line where such beverage cans typically are randomly oriented. The optical inspection system positions an optical head near the beverage cans as they move in the production line without physically interfering or interacting with the movement. The optical head senses a preselected number of different colors which appear in a predetermined field of view of each moving can. The cans being randomly oriented have different portions of the label visible in the predetermined field of view which is fixed in position. The optical head produces analog electrical signals corresponding to the intensity of each sensed color. A computer is utilized to process these analog electrical signals from the optical head.

Abstract: An optical inspection system which inspects for the presence of defects in colored labels placed, for example, on the side walls of cylindrical beverage cans. The optical inspection system utilizes a conveyor for conveying the beverage cans in a production line where such beverage cans typically are randomly oriented. The optical inspection system positions an optical head near the beverage cans as they move in the production line without physically interferring or interacting with the movement. The optical head senses a preselected number of different colors which appear in a predetermined field of view of each moving can. The cans being randomly oriented have different portions of the label visible in the predetermined field of view which is fixed in position. The optical head produces analog electrical signals corresponding to the intensity of each sensed color. A computer is utilized to process these analog electrical signals from the optical head.

Abstract: An apparatus and method for inspecting transparent objects is disclosed. The apparatus employs preconditioned radiation to detect defects having small radii of curvature or other such highly refractive surfaces and discriminate them from desirable markings having larger radii of curvature. The apparatus comprises a radiation source, means for selecting angular spectrum ranges, means for modifying average angles of incidence, radiation detection means and processing means.

Abstract: The present invention utilizes back lighting optics to produce converging white light over an area larger than an area of the edge of the convex object being profiled by the present invention. Opposite the back lighting optics are located a shadow image detector which detects the shadow image of the edge of the convex object, which is located between the back lighting optics and the shadow image detector. The detector generates a plurality of pixel outputs from each of a plurality of vertical locations for the shadow image of the edge. A rotating stage provides relative movement between the convex object and the detector/optics arrangement. The output of the detector which is a high resolution camera is fed into a data processing system which determins a sub-pixel distance measurement for each of the plurality of vertical locations and arranges the sub-pixel distance measurements into rows and columns to construct a surface profile of the convex object.

Abstract: A portable shock-proof instrument for determining the presence of defects in the surface profile of a container. The instrument includes a portable housing having shock-mounted therein an optical table carrying a point source of light, mirrors for reflecting the light in an inverted U-shaped path thereby providing compactness to the instrument, a lens in the middle portion of the U-shaped path for collimating the light and directing it past an edge of the container thereby producing a shadow image of the edge, a rotating stage for selectively turning the container, a cylindrical telescope for magnifying the horizontal field of view of the shadow image in order to enhance the detection of defects, and a camera for capturing a plurality of shadow edge images as the container is being turned. A processor is connected to the rotating stage and to the camera for analyzing the captured plurality of shadow edge images for the presence of defects.