157 results about "Neutral density filter" patented technology

A method and apparatus for achieving high-dynamic range operation with a set of spatially distributed pixel cells is provided. A pixel array with a row of pixels having apertures of varying sizes in a metal mask formed thereon controls the sensitivity of each pixel cell to light. A neutral density filter having varying light transparency values is also provided over the set of pixel cells to control the sensitivity of each pixel cell to light. The pixel cells voltage outputted is combined to obtain high-dynamic range operation.

A full-color organic light-emitting diode (OLED) device, comprising: a) a plurality of light emitting OLED pixels, each pixel having three or more color light-emitting elements for emitting different colors of light specifying a gamut and at least one additional light-emitting element for emitting a color of light within the gamut and wherein the power efficiency of the additional element is higher than the power efficiency of at least one of the three or more gamut elements; and b) a patterned neutral density filter selectively filtering the emitted light from the additional light emitting element.

A laser line probe (LLP) configured to measure an object is provided. The LLP includes a projector, a camera, a bracket, and an electronic circuit. The projector includes a light source, a first lens system and a continuously varying neutral density filter. The projector is configured for generating a line of light having a substantially even intensity distribution and for projecting the line of light onto the object. The camera includes a second lens system and a photosensitive array. The second lens system is configured to collect the light reflected by or scattered off the object as a first collected light and to image the first collected light onto the photosensitive array. The electronic circuit includes a processor and is configured to determine three-dimensional coordinates of a plurality of points of light projected on the object by the projector.

The present invention relates generally to both a system and method for visually (e.g., via a video-based system or some other visual system) monitoring one or more objects where such objects are obscured by a high intensity light source such as a plasma, flame, or welding arc. In one embodiment, a system in accordance with the present invention comprises a digital camera, at least one light emitting diode (LED) light source, and at least one filter. In another embodiment, a system in accordance with the present invention comprises a digital camera, at least one light emitting diode (LED) light source, and at least one filter selected from a notch filter, a neutral density filter, or combinations thereof. Additionally, the system of the present invention can further include software designed to process, interpret and/or collect various data captured by the visual monitoring, or, imaging, system of the present invention.

A stable light source device is provided with a light source, a pinhole constricting optical flux emitted from the light source, a first integrating element inside which optical flux from the pinhole is multiply reflected, a light detection sensor monitoring a light amount, a control section controlling the light source on the basis of the light amount monitored by the light detection sensor and making the light amount consistent, an aperture formed in the first integrating element and emitting light outside the first integrating element, a diffusion-transmission member disposed at a light emission side of the aperture, a branching section disposed at a light emission side of the diffusion-transmission member and branching incident light towards plural light emission portions, and neutral density filters provided at the light emission portions, transmitted light amounts thereof respectively differing such that light amounts at the light emission portions are respectively different.

A process for formatting rivalrous fusible images having similarly shaped stimuli of similar binocular luminance and having other similarly shaped stimuli of different binocular luminance, which metamorphose during perception into identifiable shapes that distinguish fusion from suppression. The preferred embodiment is an invertible stereoscope for viewing rivalrous images, non-rivalrous images, and stereograms, having adjustable eyepieces, lighting control of front and rear chambers, and lighting control of right and left sides. In a further preferred embodiment, rivalrous stimuli in a complementary color scheme are viewed on printed material or on a computer screen through lenses of complementary colors. Neutral density filter placement that asymmetrically attenuates light to the eyes for detection of sub-threshold afferent defects is disclosed.

An optical thin film stack provides reflection of essentially all light except for a selected amount of transmission over a selected wavelength range. Reflecting, rather than absorbing, unwanted light avoids heating caused by light absorption and allows productive use of the non-transmitted light in some applications. In some embodiments, reflector designs are “stacked” on an optical substrate to provide serial optical reflectors. Stacking dichroic filters provides reduced sensitivity to cone angle and manufacturing advantages.

The invention discloses a sinusoidal phase modulation type laser self-mixing interferometer and a measuring method thereof. The interferometer comprises a helium-neon laser, a variable neutral density filter, an electro-optical crystal modulator, a target to be measured, a photoelectric detector and a signal generator. The signal generator is used for generating sinusoidal signals with frequency of omega<m>, wherein one loop of signals is used for driving the electro-optical crystal modulator, one loop of signals is used as base-frequency signal output and the other loop of signals passes through a frequency doubler and a phase shifter and then outputs doubled-frequency signals with frequency of 2 omega<m>. The output of the photoelectric detector is amplified by an operational amplifier and then is respectively mixed with the base-frequency signals and the doubled-frequency signals to obtain two loops of signals. The signals are subject to low-pass filtering and then a computer unit controls an analog-to-digital conversion unit to acquire and demodulate a phase, so as to obtain and display the real-time displacement of the target to be measured. After the interferometer is calibrated, relative measurement accuracy of 10<-6>*L can be obtained, the measurement uncertainties within the measurement ranges of 100mum and 300mum are respectively 10nm and 0.15mum, and the measurable speed range is 0-60mm/s.

The quality of a planar image is improved while maintaining the parallax of a stereoscopic image. An image capturing device includes an imaging element that performs photoelectric conversion on respective light fluxes passing through different regions of a single pickup lens. The image capturing device includes a neutral density filter an AE control unit that acquires subject brightness, and a diaphragm control unit that, in a case of the stereoscopic pickup, controls whether or not to reduce the amount of light which reaches the imaging element using the neutral density filter based on the subject brightness, and that, in a case of the plane pickup, causes a diaphragm value of the diaphragm to be greater than a diaphragm value in the case of the stereoscopic pickup while setting the light extinction filter to a non-insertion state.

This laser height measuring device is provided with: a laser height sensor (6) comprising a laser beam irradiation section (61) for emitting a laser beam (L1) and a reflected light detection section (62) for detecting the laser beam reflected off an object to be irradiated; a sensor movement mechanism (head drive mechanism (41-43)) for moving the laser height sensor (6) within a plane; an imaging camera (component camera (5)) that is provided at a predetermined calibrating position (light incidence axis (AO); a neutral density filter (71) that allows the laser beam (L1) to pass while attenuating the laser beam; a laser beam imaging means that positions the laser height sensor (6) at the calibrating position (AO), emits the laser beam (L1), and captures an image of the laser beam which has passed the neutral density filter (71) using the imaging camera (5) in order to obtain a laser beam image; and a correction value acquisition means that obtains values for correcting the coordinates of the laser beam on the basis of the position of the laser beam in the laser beam image. Thus, the measuring position can be controlled accurately, and the accuracy of measuring position control can be maintained without requiring a sensor installation position adjustment mechanism or a positional adjustment operation.

The invention discloses a concentration measuring device and method for dust in large diameter range. Aiming at the shortcoming that scattering integration method in the prior art is not applicable when the particle size is smaller than 10 microns, the measuring device uses a multistep neutral density filter to attenuate transmission light and scattered light to a same light intensity level, realizes simultaneous shooting of transmission light and scattered light in a measurement system of a single digital area-array camera, and has the advantages of high sensitivity, fast response and simple and compact optical system. According to the obtained information of scattered light and transmission light, the distribution of particle size can be acquired; with the known particle size distribution, a method combined scattered light with scattering integration can be used to measure dust concentration of micron level, and a method combined transmission light with light extinction can be used to realize the measurement of dust concentration of submicron and nanometer levels. The invention successfully realizes the measurement of dust concentration of micron, submicron and nanometer levels, covers large particle size range, and has great market advantage.

The invention discloses a system for testing the diffraction efficiency of an acousto-optic tunable filter (AOTF). The system comprises a wavelength tunable laser, a neutral density filter, a diaphragm orifice, a beam splitting mirror, a two-dimensional electric turnplate and an energy meter. The wavelength tunable laser can generate laser beams with continuously adjustable wavelength, the laser beams after passing through the neutral density filter and the diaphragm orifice are split into two beams of lasers with fixed beam splitting ratio by the beam splitting mirror, and the energy of reflecting beams is used as reference energy; transmission beams enter the AOTF, the energy of diffracted light is received when radio-frequency drive is applied to the transmission beams, and energy with direct penetration is received when the drive is not applied to the transmission beams, thereby calculating the diffraction efficiency of the AOTF. Meanwhile, the measurement of an aperture angle can be realized by changing the angle of incident light through the two-dimensional electric turnplate. The device has the characteristics of simple principle and strong operability, can meet the requirement of testing the continuous wavelength of the AOTF and can also enhance the testing accuracy greatly by utilizing reference beams generated by the beam splitting mirror.

The invention discloses a coherent self-adaptive optical aberration correction system. The system comprises a laser light source, a reflective mirror, a spatial light modulator, and a neutral density filter, a half-wave plate and a beam expanding lens that are sequentially disposed in an incident light path of the reflective mirror. The reflected light of the reflective mirror serves as incident light of the spatial light modulator, and an angle between the incident light and the reflected light of the spatial light modulator is controlled by means of the reflective mirror. The control over coherent emphasis and coherent weakening of two light beams, regulation and control on the phase position of one of the two light beams can be achieved, so aberration correction of a microscopic system is achieved. A reference light source needs not to be implanted in sample, and the aberration correction speed is fast, so the system is quite suitable for deep aberration correction imaging of an in vivo sample.

The invention discloses a micro-scale initiating explosive device ignition temperature field measuring device and a temperature measurement method thereof. The micro-scale initiating explosive device ignition temperature field measuring device comprises an image capture light path system, a mechanical installation device, a computer and software. The image capture light path system comprises a neutral-density filter, an imaging lens and a high-speed camera; the mechanical installation device comprises a light-shading installation box, a window fixed ring, a guide rail, a sliding block, a supporting rod, a fixture, a camera installation platform and the like; and the computer and the software comprise the computer, a data transmission line, temperature measurement processing software and the like. The neutral-density filter is used for uniform filtering in a wave band of 400 to 700 nm, and the upper limit of temperature measurement can be improved, so that the light intensity is prevented from being too high to measure the temperature. The imaging lens and the high-speed camera are used for capturing image signals, the light-shading installation box can prevent the influence of environmental false light, and all components and parts can be fixed by the guide rail, the sliding block, the supporting rod, the fixture, the camera installation platform and the like, so that measurement alignment is guaranteed; and the computer and the software can be used for processing images during standardization and measurement.

A three (or more) polarizer arrangement is used to demonstrate a wide-angle variable-neutral-density (VND) filter that has both contrast uniformity and color uniformity. According to one embodiment, the outer polarizers effectively counter-rotate with respect to a fixed center polarizer as a means of compensating for transmission non-uniformity associated with geometrical polarization distortions experienced by off-normal rays. In particular, the achromatic compensation arrangement enables angle uniformity relative to normal-incidence transmission when the number of stops of attenuation grows large (e.g. 10-stops, or OD3). The filters are useful for cameras or instrumentation allowing mechanical or electromechanical tuning.

The invention discloses a double-wavelength differential near-infrared non-invasive glucose meter. The double-wavelength differential near-infrared non-invasive glucose meter comprises a laser device I (11), a plane mirror I (12), a protective layer (13), a sample (14), a function generator (15), a laser device II (16), an optical neutral density light filter (17), a parabolic mirror I (18), a plane mirror II (19), a phase-locked amplifier (110), a broadband optical near-infrared detector (111), a double-channel optical filter (112) and a parabolic mirror II (113), wherein the optical neutral density light filter can be used for adjusting the power of the laser device II (16), so that the output power ratio of the laser device I (11) to the laser device II (16) is adjusted; and the phase difference is controlled by the function generator (15) and the phase-locked amplifier (110). The double-wavelength differential near-infrared non-invasive glucose meter not only has non-invasive detecting capacity, but also has high measuring precision, especially within a hypoglycemic range by combining the amplitude and the phase characteristics of the near-infrared light and utilizing the crest and trough variation difference of absorption spectrum. Meanwhile, the protective layer is provided for preventing the laser devices from accidently injuring skin tissues.