摘要:
A spatially resolved map of the eye's refractive characteristics are provided by measuring the eye's refractive characteristics on a point-by-point basis across the anterior surface of the eye. This spatially resolved refraction data may be obtained subjectively by providing a reference pattern and a measurement beam, by establishing a particular position on the cornea as the location to be measured and manipulating the orientation of the measurement beam at that measurement point to bring the measurement beam to a desired position relative to the reference image. When the patient indicates that the measurement beam is in the desired position relative to the reference pattern, the orientation of the beam is recorded as the refractive data for that measurement point and the process proceeds to another measurement point. This provides relatively rapid, physiologically accurate refractive data on a spatially resolved basis. Alternatively, this spatially resolved refraction data may be obtained objectively by independently controlling the position and orientation of a measurement beam and using a feedback null system to determine the refractive characteristics. This enables rapid, automatic non-subjective determination of the refractive characteristics of the eye and thereby provides the ability to provide improved correction of the eye. This spatially resolved refraction information enables spatially resolved correction of vision by spatially resolved shaping of the anterior surface of the eye.
摘要:
Eye alignment is determined by producing a combined iris/retinal image by use of an imaging system. The relative position of the centroid of the pupil and various structures on the retina is indicative of the eye alignment. The eye alignment may be determined by comparing a combined iris/retinal image at the present time with a stored iris/retinal image at a past time. The imaging system may be a laser scanning ophthalmoscope.
摘要:
An instrument to make simultaneous accurate measurements of the intensity of light in each of two (or more) spectral channels using a single interference filter employs mirrors or prisms to break up the observed light beam into two (or more) beams, propagating in slightly different directions. The angle dependence of the filter spectral passband provides two distinct spectral channels which are focused onto separate detector elements. Advantages of this instrument are illustrated by its application for remote point Raman temperature measurements in hot gases.
摘要:
An input/output port for a lasing medium to minimize wavefront distortion of a coherent light beam is described. The input/output port includes an end surface integral the medium and a first port surface integral the end surface. The first port surface is substantially perpendicular to a plane normal to the longitudinal axis extending through the medium so that each ray of a beam of coherent electromagnetic radiation lying in a plane of a thickness of the beam may impinge on the port surface at a substantially equal angle with respect to reference planes normal to the port surface at the points of impingement.
摘要:
Automated grinding is performed using a tracking means having a sufficient field of view to locate edges to be processed and using a high resolution profiler in order to provide grinding information for calculation of the amount of material which should be removed from the workpiece. Those sections of the workpiece not requiring additional grinding may be traversed at a high speed in order to improve productivity. A process control computer receives grinding information from the tracking means and high resolution profiler and uses it to control a manipulator to adjust the travel speed of the grinder, force with which a grinder is applied, position of the grinder, and/or speed of rotation of the grinder in order to remove the correct amount of material from a workpiece. The technique is especially advantageous in removing excess material, burrs, nicks, chips and other minor irregularities in workpieces. A second profiler may be used to check that the grinder has properly ground portions of the workpiece. The tracking means and the profilers are flying spot laser profilers. The technique can accommodate either force-control or position-control grinding.
摘要:
An imaging system responsive to focused laser light includes a focusing lens for focusing the laser light and a mirror having a reflective side, a non-reflective side, and a hole for passing a predetermined portion of the laser light from the focusing lens through the non-reflective side. A fiber probe excites and couples fluorescence from an analyte. The fiber probe has a fiber front face for receiving laser light through the hole and for directing the fluorescence to the reflective side of the mirror. Optical devices for imaging the portion of the fluorescence reflected by the mirror to form an image of the fiber front face are provided, as well as an optical stop having an aperture in the image plane of the imaging means for reducing undesired light from the imaging means before reaching a detector. The mirror is angled for directing substantially all fluorescence from the the fiber probe into the imaging means rather than back toward the fiber probe.
摘要:
An apparatus for producing a tape superconductor of a compound superconductor type wherein the apparatus includes a first wire constructed of the superconducting compound material which is melted to form a bead. The bead is then wiped on a tape substrate to form a layer as the substrate is fed by the bead. Finally, the layer is cooled and a tape superconductor is formed.
摘要:
Automated grinding is performed using a tracking means having a sufficient field of view to locate edges to be processed and using a high resolution profiler in order to provide grinding information for calculation of the amount of material which should be removed from the workpiece. Those sections of the workpiece not requiring additional grinding may be traversed at a high speed in order to improve productivity. A process control computer receives grinding information from the tracking means and high resolution profiler and uses it to control a manipulator to adjust the travel speed of the grinder, force with which a grinder is applied, position of the grinder, and/or speed of rotation of the grinder in order to remove the correct amount of material from a workpiece. The technique is especially advantageous in removing excess material, burrs, nicks, chips and other minor irregularities in workpieces. A second profiler may be used to check that the grinder has properly ground portions of the workpiece. The tracking means and the profilers are flying spot laser profilers. The technique can accommodate either force-control or position-control grinding.
摘要:
An optical sensor head has deep, pitched grooves or screw threads in the walls of the gas channel, and a gas flow swirled along the grooves to protect optics against atmospheric debris and moving particles such as is generated by an industrial process. The grooves are pitched to support swirling motion of the gas. Use of swirled flow increases allowable flow velocity and diverts incoming particles toward the channel walls. The windows of an optical profiler, for instance, are protected against the smoke and weld spatter created by a metal-inert-gas welding torch.
摘要:
The optical properties of circular prisms, which are also known as axicons, are utilized in optical systems that generate one or more quiescent, steady in time, sharply focused circular and arc-shaped patterns of light. A laser beam incident on the circular prism is deviated by the prism effect and the emerging beam focused onto a target surface by a spherical lens or zoom lens; the radius of the circle is conveniently adjusted. Systems with stationary optics are described to efficiently form two concentric, uniform circles, or two offset circular or approximately circular arcs, from input beams derived from one or two lasers. These structured light patterns are used in tracking an edge or groove, for instance to locate the workpiece joint in robotic arc welding.