Abstract: A wavefront measuring system and method for detecting phase aberrations in wavefronts that are reflected from, transmitted through or internally reflected within objects sought to be measured, e.g., optics systems, the human eye, etc. includes placing a reticle in the path of a return beam from the object, and placing a detector at a diffraction pattern self-imaging plane relative to the reticle. The diffraction pattern is analyzed and results in a model of the wavefront phase characteristics. A set of known polynomials is fitted to the wavefront phase gradient to obtain polynomial coefficients that describe aberrations in the object or within the wavefront source being measured.

Abstract: A wavefront measuring system and method for detecting phase aberrations in wavefronts that are reflected from, transmitted through or internally reflected within objects sought to be measured, e.g., optical systems, the human eye, etc. includes placing a reticle in the path of a return beam from the object, and placing a detector at a diffraction pattern self-imaging plane relative to the reticle. The diffraction pattern is analyzed and results in a model of the wavefront phase characteristics. A set of known polynomials is fitted to the wavefront phase gradient to obtain polynomial coefficients that describe aberrations in the object or within the wavefront source being measured.

Abstract: This invention enables measurement of the imaging performance (e.g., wavefront aberration) of a projection optical system in a projection exposure apparatus. A light intensity distribution detection device measures light which emerges from a transmission portion (11) and passes through a projection optical system (10) and a transmission portion (17T) formed-in a mask (17M) while a mask (12) having the transmission portion (11) is moved along the object-side focal plane of the projection optical system (10), thereby obtaining the imaging performance of the projection optical system (10) on the basis of the measurement result.

Abstract: In a process for automatically determining the modulation transfer function (MTF) of a focal plane array (FPA) cameras, a test grid is used to generate a beat whose amplitude corresponds to that of the grid image to be measured, without the sampling MTF. (The image of the test grid has a spatial frequency in the detector plane that is detuned with respect to the Nyquist frequency of the detector array. The test grid covers a range of at least half a beat period, and then, regardless of the actual phase position, the modulation amplitude is determined therefrom. Comparative MTF measurements are thereby permitted without the influence of the sampling effect of an FPA, and particularly the MTF measurement in real time suitable for the application to moving images.

Abstract: A system and method are described for automatically determining the modulation transfer function (MTF) of an optical system. In accordance with exemplary embodiments of the present invention, optical information is collected from the optical system by imaging a bar target having at least one associated frequency to provide a bar target image for a first focus setting of the optical system. A first MTF of the optical system is determined for the at least one associated frequency at the first focus setting from the bar target image. The steps of collecting and determining are repeated by automatically selecting at least a second focus setting of the optical system to determine at least a second MTF for the at least one associated frequency. An MTF for the at least one associated frequency of the optical system is determined by interpolating the first and at least second MTFs.

Abstract: The present invention provides extended depth of field or focus to conventional Phase Contrast imaging systems. This is accomplished by including a Wavefront Coding mask in the system to apply phase variations to the wavefront transmitted by the Phase Object being imaged. The phase variations induced by the Wavefront Coding mask code the wavefront and cause the optical transfer function to remain essentially constant within some range away from the in-focus position. This provides a coded image at the detector. Post processing decodes this coded image, resulting in an in-focus image over an increased depth of field.

Abstract: Apparatus for the spatially resolved determination of the refractive power distribution of an optical element, with a light source unit for illuminating the optical element with an extended pencil of rays, includes a first multi hole screen for the production of a first number of beam pencils, a spatially resolving detector, and a computing unit. A controllable manipulator is arranged before or after the first multi hole screen. The first multi hole screen and the manipulator are transmissive only for a second number of beam pencils, the second number being smaller than the first number but greater than unity. The measurement principle of the apparatus corresponds to that of a Hartmann wavefront sensor.

Abstract: In order to provide an optical sampling waveform measuring apparatus which can measure an ultra-high speed optical signal accurately by using a stable, narrow pulse, and a low timing jitter sampling optical pulse, an optical sampling waveform measuring apparatus is provided with a passive mode-locked fiber ring laser for generating a sampling optical pulse and a cavity length varying device which adjusts the cavity length in a passive mode-locked fiber ring laser.

Abstract: An inspection system for performing a test selected from the group consisting of field of view, angle of view, distortion, image quality, depth of field, illumination system transmission efficiency, illumination profile, relative transmission of imaging system and centering error of a rigid, rod lens endoscope. The inspection system includes a testing station supporting a plurality of targets for measuring an optical performance of the endoscope, and a controller controllably displacing the testing station linearly toward and away from the endoscope and rotating the testing station at a nominal angle of view of the endoscope about a first axis and rotating the targets about a second axis parallel to the first axis to selectively displace each of the targets into the field of view of the endoscope.

Abstract: A Method to adjust the Ranging of the Modulation Transfer Function, MTF, of a Sensing System, more specifically, it provides for the preparation of a Test Chart of Modulation Transfer Function, of standard specification, and further, for the detection of the Modulation Transfer Function, MTF, for positions differing in picture depths, based on the location and size of said Test Chart, or alternatively on a variation in the thickness of the Crown Glass, whereby the acquisition of an applicable ranging of picture depth is achievable, which in turn provides a method of prompt derivation of a ranging scope of picture depths accommodating easy operation in the course of focal adjustment in workshop production of scanners.

Abstract: There are provided an optical transfer characteristic measuring method and apparatus capable of measuring an optical transfer characteristic of an optical device on optical frequency axis in wide optical frequency bandwidth with high resolution. There are provided a variable wavelength sweep type light source capable of switching the wavelength of an optical signal generated therefrom stepwise and sweeping the optical frequency of the optical signal in a predetermined frequency range, and a variable wavelength reference light source capable of switching the wavelength of an optical signal generated therefrom stepwise and not capable of sweeping the optical frequency of the optical signal.

Abstract: A variable field angle and test patern spatial frequency optical assemblage for testing a lens having a plurality of field angles employs an improved modulation transfer function (MTF) design system for evaluating image quality produced by the lens being tested. A reflecting surface capable of translational and rotational movements is arranged along a predetermined optical path for receiving a collimated array of light rays and then directing the collimated array of light rays to the lens being tested.

Abstract: The Dynamic Bendloss Measuring Device allows easy, repeatable determination of the bend sensitivity of a single-mode optical fiber by subjecting the fiber to dynamically changing bend angles under varying degrees of tension and bend diameters. It utilizes a swing arm capable of sweeping an arc subtending a range of angles at any given bend diameter and fiber tension and calculating the bendloss from the light attenuation at each degree of the range. The varying bend diameters are provided by pins of diverse diameters that are singly inserted into an adjustably-sized aperture while the variation in the applied tension can be effected by changing the input current setting in the tension assembly. With each new pin and tension setting, the swing arm sweeps through the pre-selected range of bend angles, resulting in varying degrees of attenuation of light.

Abstract: Apparatus for the spatially resolved determination of the refractive power distribution of an optical element, with a light source unit for illuminating the optical element with an extended pencil of rays, includes a first multi hole screen for the production of a first number of beam pencils, a spatially resolving detector, and a computing unit. A controllable manipulator is arranged before or after the first multi hole screen. The first multi hole screen and the manipulator are transmissive only for a second number of beam pencils, the second number being smaller than the first number but greater than unity. The measurement principle of the apparatus corresponds to that of a Hartmann wavefront sensor.

Abstract: There are provided a method of evaluating the reflection performance of a reflecting mirror designed for a vehicle lamp, an evaluation system, and a computer-readable storage medium. There are provided steps (108a) and (108b) in the method. The step (108a) is provided so as to enter design information representative of a plurality of reflecting basic surfaces as well as position information of a light source in a vehicle lamp. The step (108b) is provided so as to display attribute information with respect to each of a plurality of areas into which one reflecting basic surface selected from among the reflecting basic surfaces is divided on the basis of design information. The attribute information indicates whether imaginary light from the light source position can effectively reach each area, and is applied to a reflecting mirror composed of the plurality of reflecting basic surfaces.