Abstract:
It is an object of the present invention to provide a method and a device for automatically calibrating a light intensity measurement device. The device (1) includes an optical switch (3) for switching a route of output from an optical intensity modulator (2), an optical attenuator (5) arranged on a first waveguide (4), a second waveguide (6), a light intensity measurement device (7), a control device (8) for receiving light intensity information measured by the light intensity measurement device (7) and controlling the signal to be applied to the optical intensity modulator (2), and a signal source (9) for receiving a control signal of the control device (8) and adjusting the signal to be applied to the optical intensity modulator (2).
Abstract:
An instrument for measuring the angular distribution of light produced by an illumination system of a microlithographic projection exposure apparatus comprises pinhole (82) and a polarization conversion unit (92), for example a quarter-wave plate, that converts at least one state of polarization of the light into a circular state of polarization. An irradiance sensor (96) such as a CCD image sensor detects the spatial distribution of light having passed the pinhole (82) and being in a circular state of polarization. An aspheric collimating lens (90) may be arranged between the pinhole (82) and the polarization conversion unit (92).
Abstract:
A method and system for characterizing and quantifying various error and calibration components of signals associated with photo-detectors. By varying the detector operational parameters such as input light intensity and integration times, measured signals can be analyzed to separate out and quantify various components of the measured signals. The various components thus determined may be categorized according to their dependencies on the operational parameters. Such component characterization allows better understanding of the detector system and ways in which such system can be improved so as to yield an improved measurement result for which the detector is being utilized.
Abstract:
A method for imaging a sample by means of a device having a cavity with black inner walls and a sample opening, the device further comprising illumination means for illumination of the cavity and a digital imaging device directed from the cavity to the sample opening, the method comprising the following steps : - presenting a sample to the cavity via a sample opening; - illuminating the cavity; - activating the imaging device to record an image of the sample; - communicating the recorded image data to a computer programmed with image analysis software to analyze the recorded image, characterized in that the inner wall of the cavity is light absorbing and in that it is at least partly provided with light point sources distributed over at least a part of the inner wall of the cavity and a selection of the light sources, dependent on the desired light conditions, is activated.
Abstract:
The invention relates to a light beam receiver (1) for analysing the reception of light beams by means of a plurality of light beam detector elements (112, 113) and integrators (141, 142) for light beam element-based signals (161, 162). An integration duration control system (143) having the effect of limiting signal integrality is allocated to at least two integrators. In this way, received light beams can be analysed by their response to evaluated integrator signals (171, 172) that are related to each other.
Abstract:
A zero point adjustment is performed by generating no signal state of a CCD camera. A state in which stray light does not enter the CCD camera is ensured by a calibration shutter. An output signal of the CCD camera is transmitted to a light amount calculator, and a calibrating section executes a calibration for the light amount calculator by using an output signal value as a reference (zero point). Further, light outputted from a laser light source is attenuated by an optical attenuator and is made to be incident on the CCD camera. By switching an attenuating amount of the optical attenuator, correctly set light is made to be incident on the CCD camera. The output signal of the CCD camera is transmitted to the light amount calculator, and the calibrating section executes the calibration such that values of the respective output signals correctly correspond to respective light amounts.
Abstract:
The invention relates to a radiation sensor device comprising a housing and a plurality of radiation sensor modules secured to the housing. Each radiation sensor module comprises a radiation sensor arranged to detect radiation incident on the radiation source module. Preferably, each radiation sensor module contains an entire so-called optical train to allow for calibration of the detector (e.g., photodiodes, photoresistors and the like) without disassembling all the components of the module.
Abstract:
Disclosed is a method for correcting the temperature sensitivity of the amount of light L emitted by a light emitting diode (LED) and measured in a light detector, said LED being operated in a pulsed mode with an essentially constant pulse duration tP. According to the inventive method, a predetermined parameter X that has a predetermined ratio to the temperature T of the LED is used while a corrective factor K is determined from said parameter X, preferably using a calibration table, most preferably a closed, predetermined function, with the aid of which the measured emitted amount of light L is corrected by the temperature-dependent variations of the emitted amount of light. The parameter X is determined from at least two output signals of the LED which are correlated in a predetermined manner.
Abstract:
A system (10) provides white light having a selectable spectral characteristic (e.g. a selectable color temperature) using an optical integrating cavity (11) to combine energy of different wavelengths from different sources with white light. The cavity has a diffusively reflective interior surface and an aperture (17) for allowing emission of combined light. Control of the intensity of emission of the sources sets the amount of primary color light of each wavelength added to the substantially white input light output and thus determines a spectral characteristic of the white light output through the aperture. A variety of different elements may optically process the combined light output, such a deflector, a variable iris, and a lens a variable focusing lenses system, a collimator, a holographic diffuser and combinations thereof.