Abstract: In a method of obtaining an optical constant of each the films of a film-stacked structure formed on a substrate, a basic process obtains an optical constant of each of the films by successively providing the films one by one as a target film from bottom to top and obtaining an optical constant of the target film by using a previously obtained optical constant of a below-located film that is located below the target film and a re-obtaining process re-obtains the optical constant of each of the films by correcting the previously obtained optical constant of the below-located film and the optical constant of the target film obtained in the basic process.

Abstract: An apparatus that enables real time measurement of the spatial profile, circularity, centroid, astigmatism and M2 values of a laser beam generated by a high power laser beam. The apparatus employs the optics used in a process application, including a focus lens and cover glass. An attenuation module includes a pair of high reflecting mirror plates disposed in parallel, spaced apart relation to one another at a common angle of incidence to the laser beam. A beam dump is positioned out of a path of travel of the laser beam and in receiving relation to light reflected by the first and second mirrors. A camera detects spots of light that pass through the first and second mirrors. A high power attenuator formed by a highly reflective mirror pair is positioned between the source and the attenuation module. A second embodiment includes a single mirror plate having highly reflective surfaces.

Abstract: A method for calibrating a spectrometer, while orbiting a celestial body, includes the steps of: (a) obtaining an estimate of radiance emanating from the celestial body; (b) raster scanning the celestial body using the spectrometer; (c) measuring filtered radiance of the celestial body based on step (b); and (d) determining gain of the spectrometer using steps (a) and (c). A calibrated spectrometer of the present invention is based on the determined gain of step (d). The method includes the step of: (e) raster scanning another celestial body to determine the albedo radiance of the other celestial body, after determining gain of the spectrometer in step (d). The celestial body may be the moon and the other celestial body may be the Earth.

Abstract: The invention describes a light sensor (1) comprising a filter arrangement (11), which filter arrangement (11) comprises a number of spectral filters (F1, F2, . . . , Fn) for filtering incident light (L), wherein a spectral filter (F1, F2, . . . , Fn) is realized to pass a distinct component of the incident light (L), an aperture arrangement (12) for admitting a fraction of the incident light (L), and a sensor arrangement (13) realized to collect the admitted filtered light (L?), which sensor arrangement (13) comprises an array of sensor elements (130) for generating image-related signals (S, S1, S2, . . . , Sn) and which sensor array is sub-divided into a number of regions (R1, R2, . . . , Rn), wherein a region (R1, R2, . . . , Rn) of the sensor array is allocated to a corresponding spectral filter (Fi, F2, . . . , Fn) such that an image-related signal (S) generated by a sensor element (130) of a particular region (R1, R2, . . .

Abstract: Vehicle headlamp illumination is monitored and data is communicated to a host control unit. The host control unit implements a network accessible user interface to communicate with a user computer, which can include a graphical display of illumination information as well as a numerical indication of an automatically detected location of the edge of the headlamp beam. The network accessible user interface can also include the capability to manually audit the headlamp beam by allowing a user to specify a headlamp beam location, which will then update system parameters. The network accessible user interface may be a web-based interface where the host control unit implements a web server and the user computer is running a web browser. The system can include a collection of intelligent, independent sensor units, each incorporating a vertical array of sensing elements capable of detecting headlamp illumination.

Abstract: A direction sensor (200) includes sensor cells (215) that respectively correspond to different directions. Each of the sensor cells (215) includes a light sensor (130, 140) and a grating (120) that couples incident light into the light sensor (130, 140) when the incident light has a specific wavelength and is incident on the grating (120) along the direction corresponding to the sensor cell (215).

Abstract: A plurality of fluorescent lamps 30 are in a decentered layout so as to be placed in a peripheral part of an upper space of an environmental test chamber 11 above a sample loading surface 21. The irradiance distribution of light from the fluorescent lamps 30 over the sample loading surface 21 is in the range of ±25% relative to the irradiance at the center of the sample loading surface 21.

Abstract: A light baffle arrangement for sensors is used to limit the sensing field of view. Arranging multiple said limited view sensors in a linear array provides a means to accurately locate and analyze the position of a beam pattern along said array axis as in checking vehicle headlamp beam alignment.

Abstract: A joulemeter is capable of non-destructively measuring multiple characteristics of a laser beam. The joulemeter comprises a series of parallel probe beams, which are directed though a transparent media adjacent to an absorbing media that the tested beams pass through. Arrays of optical sensors or a chirp sensor are used to intercept and measure deflections the probe beams. A control unit renders measurements on selected properties of the laser.

Abstract: Disclosed herein is a method and apparatus for automatic correction of beam waist position drift in real time, using wafer inspection data taken during normal tool operation. Also disclosed herein is an improved laser astigmatism corrector for use either internal or external to the laser.

Abstract: A mirror structure is provided in which at least a portion of a wavefront sensor is integrated with a mirror. In particular, a mirror structure is provided in which a Hartmann mask or a microlens array of a Shack-Hartmann wavefront sensor is integrated with a mirror to provide a very compact wavefront detector/corrector in a single device. Such a mirror structure may be used in a laser cavity to simplify adaptive optics in the cavity. Furthermore, a Hartmann Mask may be integrated with self deforming mirror comprising an active PZT layer bonded to a passive mirror substrate, wherein the Hartmann Mask comprises an array of apertures formed through the active PZT layer.

Abstract: Devices and approaches for addressing wavefront corruption in biometric applications. A biometric imaging system may have a laser, a wavefront sensor, and an optical system. The laser may be configured to project a laser spot onto a skin portion of a human face, and the optical system may be configured to collect scattered light from the laser spot and relay the light to the wavefront sensor. The biometric imaging system may also have an adaptive optical element and a controller configured to provide actuation commands to the adaptive optical element based at least in part upon a wavefront distortion measurement output from the wavefront sensor. The optical system may further be configured to relay image light to an image camera of the optical system. The image camera may be an iris camera configured for obtaining iris images suitable for biometric identification.

Abstract: A machine and methods measure a characteristic of an optical signal incident upon a detector characterized by one or more dynamic response parameters. One method receives an output signal from the detector and compares that output signal and a computationally determined response of the detector to a known optical signal incident upon the detector. The response is based on said one or more dynamic parameters. The method determines the characteristic based on a relationship between the output signal and the computationally determined response. Another method observes an output signal from an optical detector detecting one or more optical signals, accesses a characteristic curve of detector response, compares the observed output signal to the characteristic curve, and calculates at least one characteristic of one or more optical signals based on a relationship of the observed output signal and the characteristic curve.

Abstract: A disclosed optical testing apparatus comprises: a plurality of optical fibers, each optical fiber having a collection end in optical communication with an output end; and a support member supporting the collection ends of the optical fibers so as to simultaneously view an examination region from different angles. A disclosed optical testing apparatus comprises a plurality of optical fibers having collection ends arranged to simultaneously view an examination region from a plurality of different angles. A disclosed optical testing apparatus comprises a plurality of optical fibers, each optical fiber having a collection end, the collection ends of the optical fibers arranged in fixed spatial relationship respective to one another to simultaneously view an examination region from different angles.

Abstract: Systems and methods for measuring stray light in a lithographic apparatus are described using Radiometric Kirk Test (also known as Scanning SAMOS Test). The Radiometric Kirk Test of the present invention involves a test pattern having an isolated dark area within a much larger bright field. The radiometric Kirk test includes at least two continuous or stepped scans of an aperture of a detector in an image plane of a lithographic system. During a dark area measurement, the aperture of the detector is positioned such that at least at one point the aperture of the detector is centered within an image of the dark area. During a bright area measurement, the aperture of the detector is positioned within the image of the bright field. The integrated detector signal is correspondingly computed for the dark area measurement and the bright area measurement.

Abstract: A method for measuring illuminance of a lamp utilizes at least one illuminance meter and a rotary apparatus. The lamp is installed on the rotary apparatus. The lamp emits light and projects onto an irradiation area. A measurement area is defined from within the irradiation area. The measurement area is evenly divided into n sub-measurement areas, wherein n is a natural number. The n sub-measurement areas are centrosymmetric. At least one illuminance meter measuring illuminance of the lamp is disposed on one of the n sub-measurement areas. The rotary apparatus drives the lamp to rotate 360/n° in turn. The single illuminance meter measures illuminance of the lamp in other (n?1) sub-measurement areas.

Abstract: An apparatus that enables real time measurement of the spatial profile, circularity, centroid, astigmatism and M2 values of a laser beam generated by a high power laser beam. The apparatus employs the optics used in a process application, including a focus lens and cover glass. An attenuation module includes a pair of high reflecting mirror plates disposed in parallel, spaced apart relation to one another at a common angle of incidence to the laser beam. A beam dump is positioned out of a path of travel of the laser beam and in receiving relation to light reflected by the first and second mirrors. A camera detects spots of light that pass through the first and second mirrors. A high power attenuator formed by a highly reflective mirror pair is positioned between the source and the attenuation module. A second embodiment includes a single mirror plate having highly reflective surfaces.

Abstract: The present invention relates to light sensors for measuring light characteristics. In particular, the present invention relates to a light directionality sensor that is capable of measuring light characteristics such as the light direction, light collimation, and light distribution. According to a first aspect of the present invention there is provided a light directionality sensor comprising a photo-sensor (2), comprising a plurality of photo-sensitive elements (3), and a plurality of light-absorbing light selecting structures (1) arranged on the photo-sensor so as to form an array of light-absorbing light selecting structures. In the array of light-absorbing light selecting structures, a succession of at least some of the light-absorbing light selecting structures has varying structural characteristics.

Abstract: A mirror structure is provided in which at least a portion of a wavefront sensor is integrated with a mirror. In particular, a mirror structure is provided in which a Hartmann mask or a microlens array of a Shack-Hartmann wavefront sensor is integrated with a mirror to provide a very compact wavefront detector/corrector in a single device. Such a mirror structure may be used with a tip-tilt stage in a laser cavity to provide much simplified adaptive optics in the cavity. Furthermore, a Hartmann Mask may be integrated with self deforming mirror comprising an active PZT layer bonded to a passive mirror substrate, wherein the Hartmann Mask comprises an array of apertures formed through the active PZT layer.

Abstract: A system, for determining characteristics of a beam wavefront and reshaping such wavefront, including: apparatus for sampling the wavefront curvature and generating outputs; apparatus for reshaping the wavefront; and apparatus for receiving the outputs, proportioning the outputs to match the inputs need to drive controls for the reshaping apparatus, and sending the proportioned outputs to the reshaping apparatus. The reshaping apparatus is, preferably, a deformable mirror. The sampling apparatus includes a distorted grating. The method includes: positioning the sampling apparatus in the bean path; positioning a reshaping apparatus in the beam path; sampling the curvature of the wavefront and generating outputs representative of the curvature thereof; sending the generated outputs to the proportioning apparatus; proportioning the outputs to match the inputs needed to drive the controls of the reshaping apparatus; and sending the proportioned outputs to the reshaping apparatus to change the shape thereof.

Abstract: Headlamp alignment is detected using a collection of intelligent, independent sensor units, each of which incorporates a vertical array of sensing elements capable of detecting headlamp illumination. The sensor units are networked together and can be coupled to a host controller. The host controller can provide a user interface via a touch screen and a Web server, and can further communicate with a plant network for interfacing with manufacturing databases. The network of sensor units can accommodate four or more sensors, which allows multiple vehicles and multiple headlamp types to be audited without physical movement of the sensor units. The sensor units are low in power consumption and can receive power over the same cable providing network communication. Incorporation of non-volatile memory within the sensor units allows factory data to be recorded within each sensor unit and permits convenient replacement of units in the field.

Abstract: The disclosure relates to microlithography systems, such as EUV microlithography illumination systems, as well as related components, systems and methods.

Abstract: Embodiments of the present invention generally relate to circuits, systems and methods that can be used to detect light beam misalignment, so that compensation for such misalignment can be performed. In accordance with an embodiment, a circuit includes a photo-detector (PD) having a plurality of electrically isolated PD segments. Additionally, the circuit has circuitry, including switches, configured to control how currents indicative of light detected by the plurality of electrically isolated PD segments are arithmetically combined. When the switches are in a first configuration, a signal produced by the circuitry is indicative of vertical light beam alignment. When the switches are in a second configuration, the signal produced by the circuitry is indicative of horizontal light beam alignment. The signals indicative of vertical light beam alignment and horizontal light beam alignment can be used detect light beam misalignment, so that compensation for such misalignment can be performed.

Abstract: A method for correcting a wave front analyzer, in which the analyzer detects a signal from an incident wave front to be analyzed (FO), the detected signal providing phase and intensity local information. The method includes correcting the phase computation according to intensity space variations. A wave front analyzer for implementing the method is also described.

Abstract: A two-stage homogenizer comprising a first homogenizer stage and a second homogenizer stage. The first homogenizer stage includes a pair of microlens arrays and associated focusing optics. The second homogenizer stage includes a second pair of microlens arrays and associated focusing optics. The second homogenizer stage is positioned to receive radiation which is output from the first homogenizer stage.

Abstract: System and method for estimating and correcting an aberration of an optical system. The method includes capturing a first plurality of images on a first plurality of planes. The first plurality of images is formed by at least the optical system. Additionally, the method includes processing at least information associated with the first plurality of images, and determining a first auxiliary function based upon at least the information associated with the first plurality of images. The first auxiliary function represents a first aberration of the optical system. Moreover, the method includes adjusting the optical system based upon at least information associated with the first auxiliary function.

Abstract: A measurement apparatus disclosed that has a radiation source configured to provide a measurement beam of radiation such that an individually controllable element of an array of individually controllable elements capable of modulating a beam of radiation, is illuminated by the measurement beam and redirects the measurement beam, and a detector arranged to receive the redirected measurement beam and determine the position at which the redirected measurement beam is incident upon the detector, the position at which the redirected measurement beam is incident upon the detector being indicative of a characteristic of the individually controllable element.

Abstract: An optical package includes a semiconductor laser, an adjustable mirror and a wavelength conversion device comprising a waveguide portion. The semiconductor laser, adjustable mirror, and wavelength conversion device are oriented to form an optical pathway between an output of the semiconductor laser and an input of the wavelength conversion device. The beam of the semiconductor laser is directed along the optical pathway and onto the adjustable mirror where the beam is reflected by the adjustable mirror onto the waveguide portion of the wavelength conversion device. The adjustable mirror may also be either thermally or mechanically deformable such that, when the adjustable mirror is deformed, the path of the beam along the optical pathway is altered thereby focusing the beam on the waveguide portion of the wavelength conversion device. The adjustable mirror may be adjusted such that the beam of the semiconductor laser is positioned on the waveguide portion of the wavelength conversion device.

Abstract: A method for detecting misalignment of a vehicle headlight using a camera system is specified. For this purpose, the headlight is in a predefined position and the camera system is arranged on or in the vehicle and is oriented in such a manner that the light distribution pattern of the headlight in front of the motor vehicle is detected. With a predefined headlight position, an actual light distribution pattern of the headlight is recorded using the camera system and is compared with a desired light distribution pattern for the predefined headlight position. If the actual light distribution pattern differs from the desired light distribution pattern, misalignment of the headlight is detected.

Abstract: An optical axis inspection apparatus is provided with: a camera for capturing a light distribution pattern of a light source device projected on a screen; an image processing device for finding a cutoff line in the light distribution pattern; an acceptance reference cutoff line setting unit; and a shade having an oblong slit and arranged to be opposed to a projection lens of the projection type light source device. Whether or not an optical axis is proper is inspected based oh a shift of the cutoff line with respect to the acceptance reference cutoff line. Only a transmissive light passing through a substantially central portion in a vertical direction of a projection lens including an optical axis of the projection lens is guided onto the screen by the shade.

Abstract: Headlamp alignment is detected using a collection of intelligent, independent sensor units, each of which incorporates a vertical array of sensing elements capable of detecting headlamp illumination. The sensor units are networked together and can be coupled to a host controller. The host controller can provide a user interface via a touch screen and a Web server, and can further communicate with a plant network for interfacing with manufacturing databases. The network of sensor units can accommodate four or more sensors, which allows multiple vehicles and multiple headlamp types to be audited without physical movement of the sensor units. The sensor units are low in power consumption and can receive power over the same cable providing network communication. Incorporation of non-volatile memory within the sensor units allows factory data to be recorded within each sensor unit and permits convenient replacement of units in the field.

Abstract: An apparatus and method for verifying a laser etch on a rubber sample. In one embodiment, the apparatus includes a tire production line, a sample holding device, a laser having a diode, and a servo-assembly. The laser of the apparatus is configured to etch indicia on a sidewall of a tire on the tire production line and is further configured to etch at least one line in a rubber sample on the sample holding device. In one embodiment, the method includes etching a production tire with a laser, interrupting the laser, moving the laser to a laser diode testing location, loading a rubber sample in a holding device, etching at least one line into the rubber sample with the laser, manually or automatically measuring a depth of the at least one line, and comparing the depth of the at least one line to an acceptable line depth range.

Abstract: A Shack Hartmann (“SH”) wavefront sensor comprising an optical device, such as a wave front dissector including a lenslet array, for transmitting, dissecting and focusing an incoming optical wave, an optical system, including, for example, an optical sensor, for receiving the transmitted incoming optical wave, and a removable kinematic mount for repeatable precision mounting of the optical device to the optical system.

Abstract: The present invention relates to a wavefront sensor using a pair of screens, each having a two-dimensional array of circular apertures, to achieve Moiré effects, and its use to measure the slope of a wavefront.

Abstract: Embodiments of the present invention relate to a wavefront imaging sensor (WIS) comprising an aperture layer having an aperture, a light detector having a surface and a transparent layer between the aperture layer and the light detector. The light detector can receive a light projection at the surface from light passing through the aperture. The light detector can also separately measure amplitude and phase information of a wavefront at the aperture based on the received light projection. The transparent layer has a thickness designed to locate the surface of the light detector approximately at a self-focusing plane in a high Fresnel number regime to narrow the light projection.

Abstract: A measurement apparatus disclosed that has a radiation source configured to provide a measurement beam of radiation such that an individually controllable element of an array of individually controllable elements capable of modulating a beam of radiation, is illuminated by the measurement beam and redirects the measurement beam, and a detector arranged to receive the redirected measurement beam and determine the position at which the redirected measurement beam is incident upon the detector, the position at which the redirected measurement beam is incident upon the detector being indicative of a characteristic of the individually controllable element.

Abstract: The invention relates to a filter device for an illumination system, especially for the correction of the illumination of the illuminating pupil, including a light source, with the illumination system being passed through by a bundle of illuminating rays from the light source to an object plane, with the bundle of illuminating rays impinging upon the filter device, including at least one filter element which can be introduced into the beam path of the bundle of illuminating rays, with the filter element including an actuating device, so that the filter element can be brought with the help of the actuating device into the bundle of illuminating rays.

Abstract: A goniophotometer includes two independent towers: a main support tower and an upright mirror tower. A swing arm is connected to the main support tower and can be rotated around a main horizontal axis. An elliptic flat rotation mirror, a first detector and a second detector are fixed to the swing arm. A test light source that is also connected to the main support tower can be rotated around a vertical axis. An upright round mirror is connected to the upright mirror tower. A far-field measurement can be achieved when a light beam from the test light source travels into the rotation mirror then is reflected to the upright mirror, and then is reflected by the upright mirror to the first detector. A near field measurement is achieved when the second detector receives a test light beam directly form the test light source.

Abstract: An aberration measurement apparatus measures the aberration of an imaging optical system. The apparatus includes an illumination system, a separation member, and a measurement unit. The illumination system supplies the imaging optical system with measurement light used to measure an aberration of the imaging optical system and background light different from the measurement light. The separation member separates the measurement light and the background light which have passed through the imaging optical system. The measurement unit measures the aberration of the imaging optical system on the basis of the measurement light separated by the separation member.

Abstract: A system for testing a reflective display device includes a testing apparatus and a computer. The testing apparatus includes one or more light emitters, one or more light detectors, an analog-to-digital converter (ADC) module, and a microcontroller unit (MCU). The light emitters are for projecting light onto a reflective display device located on the testing apparatus. The light detectors are for sensing reflected light from the reflective display device, and generating electricity according to a luminance of the reflected light. The ADC module is for receiving the electrical signals from the light detectors, and producing a digital output according to voltages of the electrical signals. The MCU is configured for reading the digital output of the ADC module. The computer is for processing the digital output and displaying results after processing.

Abstract: Light is irradiated on a light-shielding pattern on an object surface side of a projection optical system, and light intensity distribution of the light having passed through the projection optical system and slits is detected while slits of an aerial image measuring unit on the image plane side of the projection optical system are moved within a plane perpendicular to the optical axis of the projection optical system, The information concerning the flare of the projection optical system is computed from the light intensity distribution, so that the influence of resist coated on a wafer used in a conventional exposing method can be eliminated, and highly accurate measurement of information concerning the flare can be realized. Further, measurement of information concerning the flare can be performed in a short time comparing to the exposing method because development process or the like of the wafer is not necessary.

Abstract: Provided is an optical sampling apparatus that samples light to be measured having a pulse waveform, including a sampling light output section that outputs a first sampling light and a second sampling light, both having pulse waveforms of a spectrum different from that of the light to be measured; a first sampling section that includes a first nonlinear optical medium, which causes a nonlinear optical effect by causing at least a portion of the light to be measured and the first sampling light to pass therethrough and outputs light generated by the nonlinear optical effect, and that outputs at least a portion of the light generated by the nonlinear optical effect as a first output light; and a second sampling section that includes a second nonlinear optical medium, which causes a nonlinear optical effect by causing at least a portion of the first output light and the second sampling light to pass therethrough with a temporal overlap in order to output light generated by the nonlinear optical effect, and that

Abstract: A system and method are used to detect parameters regarding an exposure portion or an exposure beam. The system comprising a substrate stage and a metrology stage. The substrate stage is configured to position a substrate to receive an exposure beam from an exposure portion of a lithography system. The metrology stage has a sensor system thereon that is configured to detected parameters of the exposure system or the exposure beam. In one example, the system is within a lithography system, which further comprises an illumination system, a patterning device, and a projection system. The patterning device patterns a beam of radiation from the illumination system. The projection system, which is located within the exposure portion, projects that pattered beam onto the substrate or the sensor system.

Abstract: An enhanced detection system can eliminate use of a sheath fluid by selecting which particles that pass through an sensing region to detect parametric characteristics thereof based upon position of each particle while it is in a sensing region relative to one or more predetermined positions, such as an in-focus position relative to one or more light beams directed into the sensing region, to enhance accuracy and robustness of particle parametric characteristics detection.

Abstract: The present invention relates to a beam analyzing system and a method for analyzing pulsed particle or laser beams. The inventive beam analyzing system comprises a detector unit, a unit for generating a pulsed reference laser beam, a first electro-optical modulator and a first read-out photo detector, wherein the optical input of the first electro-optical modulator is connected with the unit for generating a pulsed reference laser beam, wherein the optical output of the first electro-optical modulator is connected with the first readout photo detector and wherein the signal input of the first electro-optical modulator is connected with the detector unit.

Abstract: An optical triangulation measuring device includes an emmiter that emits two alternating light beams with different wavelengths along the same path; a beam splitter; an optical separator that directs the alternating split beams towards the surfaces from which they are reflected; an optical combiner that collects the beams and directs them along a path; optronic sensors that receive two light images and to deliver a signal indicating the position of the energy barycenter a time synchronizer for the two alternating beams and the two images on the optronic sensors; and a processor for processing the signals from the optronic sensors in order to supply information relating to the position and inclination of the surface.

Abstract: A measure of the quality of a laser beam is obtained by comparing the power of a theoretical Gaussian beam through a (certain sized area) pinhole to the power of a test beam through a same sized (area) pinhole. The theoretical surrogate Gaussian beam with the same second moment of intensity as the test beam is used to determine the “bucket size” used in “power-in-the-bucket” techniques. The bucket size is an interaction area determined by the wavelength of the laser light, the focusing distance, and the 1/e2 radius of the near field intensity. The beam quality is determined by taking the square root of the ratio of the theoretical power through a bucket and the actual power through a pinhole with the same size as the bucket. The beam quality of different types of beam profiles can be obtained with a single method or measure.

Abstract: The invention provides an apparatus for sampling and determining characteristics of a light source. The apparatus comprises a sensor system configured to sample the spatial and spectral radiation characteristics of the light source and a goniometer that is configured to desirably control and adjust the relative position between the sensor system and the light source. The goniometer is configured to position the sensor system relative to the light source using two or more degrees of freedom. The apparatus additionally includes a control system configured to control the operation of the sensor system and the sampling of the spatial and spectral radiation characteristics of the light source. The control system is further configured to control operation of the goniometer for the relative positioning of the sensor system and the light source.

Abstract: A method for determining a polarization state of light passed through the projection lens of a lithographic apparatus is described. Polarizing structures are disposed on an object side of the projection lens of the lithographic apparatus. By measuring light that has passed through the polarizing structures information regarding the polarization characteristics of the projection lens can be determined.

Abstract: Determining relationships between one laser beam and an object onto which such beam is directed including: directing such beam onto the object; collecting radiation from the beam that is reflected back; spectrally discriminating the collected, reflected radiation from other collected radiation; generating an image of the collected beam radiation; and analyzing this image to determine the value of at least one parameter selected from: the diameter of the beam on the object; the position of the beam on the object; and beam quality on the object. The determined value(s) may be used to adjust parameter(s) of the beam. Additional steps include directing a second beam onto the object and collecting, spectrally discriminating, generating an image and analyzing it to determine the value of at least one parameter related to the second beam. The forgoing may also include utilizing the determined second value to adjust parameter(s) of the second beam.