We present a new technique for measuring the modulation transfer function (MTF) of a focal plane array (FPA). The main idea is to project a periodic pattern of thin lines that are canted with respect to the sensor'...
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We present a new technique for measuring the modulation transfer function (MTF) of a focal plane array (FPA). The main idea is to project a periodic pattern of thin lines that are canted with respect to the sensor's columns. Practically, one aims the projection by using the self-imaging property of a periodic target. The technique, called the canted periodic target test, has been validated experimentally on a specific infrared FPA, leading to MTF evaluation to as great as five times the Nyquist frequency. (C) 1999 Optical Society of America OCIS codes: 100.2550, 110.3080, 110.4100, 110.6760.
The modulation transfer function (MTF) is the tool most commonly used for quantifying the performance of an electro-optical imaging system. Hexagonal sampling strategy for detector arrays can provide an improvement ov...
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The modulation transfer function (MTF) is the tool most commonly used for quantifying the performance of an electro-optical imaging system. Hexagonal sampling strategy for detector arrays can provide an improvement over rectangular sampling, thus the hexagonal pixel array detector is designed with hexagonal pixel and hexagonal sampling. In this paper, firstly, two dimensional MTF model of a hexagonal pixel array detector is deduced according to its definition. Then, the MTF of an imaging system with such a detector is established. Additionally, the MTFs of detectors with other shaped pixel geometry, but with the same photosensitive areas are compared. The results show that the values of hexagonal MTF are obviously larger than those of rectangular and triangular pixel array detectors at the same frequencies. In addition, with the increase of the atmospheric coherence length, the MTF values of the system become larger, and the system imaging capability will be improved.
Transparent luminescing screens can be used as image transducers in radiographic and image-intensifier systems. The modulation transfer function (MTF) and efficiency of these screens when used in conjunction with a re...
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Transparent luminescing screens can be used as image transducers in radiographic and image-intensifier systems. The modulation transfer function (MTF) and efficiency of these screens when used in conjunction with a receiver or recording medium are obtained from the derivation of the point spread function of the screen–receiver system. The derivation accounts for all optical paths and attenuations of the luminescent energy producing the spread function. Both the theoretical MTF’s and energy-transducing efficiencies of several screen–receiver systems are presented for various system parameters. The MTF of an actual (ZnS) screen–film system, computed from this derivation, was found to be in excellent agreement with the MTF of the system determined by photographic photometry.
The quality of the image produced by optical reflectarrays as a function of the F/#, polarization, and wavelength is analyzed in this paper. The results are expressed as monochromatic and polychromatic modulation tran...
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The quality of the image produced by optical reflectarrays as a function of the F/#, polarization, and wavelength is analyzed in this paper. The results are expressed as monochromatic and polychromatic modulation transfer functions. They show that large aperture multilevel reflectarrays perform quite close to the diffraction-limited case. The chromatic aberrations make these elements highly wavelength-selective. (C) 2011 Optical Society of America
The modulation transfer function (MTF) is one of the most complete tools to study the optical performance of the eye. We present the average radial MTF profiles measured in 68 subjects grouped in six age ranges (from ...
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The modulation transfer function (MTF) is one of the most complete tools to study the optical performance of the eye. We present the average radial MTF profiles measured in 68 subjects grouped in six age ranges (from 20 to 80 years) and a general formula to estimate the radial profile of human MTF as a function of pupil size and age. The mean MTF for each age group was fitted to an analytical expression to compute two parameters related to aging. The proposed formula fitted reasonably well to experimental data available in previous works and predicted the average changes with aging of different optical quality parameters obtained from MTF. (c) 2023 Optica Publishing Group
Mid-wavelength Infrared (MWIR) and long-wavelength infrared (LWIR) Barrier Infrared Detector (BIRD) based on Antimonides Type-II superlattice detector array material are hybridized to 640 x 512, 1024 x 1024 and 1344 x...
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Mid-wavelength Infrared (MWIR) and long-wavelength infrared (LWIR) Barrier Infrared Detector (BIRD) based on Antimonides Type-II superlattice detector array material are hybridized to 640 x 512, 1024 x 1024 and 1344 x 784 pixels format read out integrated circuits. The focal plane arrays (FPAs) Noiie Equivalent Temperature Difference (NE Delta T), Quantum Efficiency (eta), Dark Current Density (J(D)), and modulation transfer function (MTF) performance were measured at operating temperatures. High performance 640 x 512 array format MWIR High Operating Temperature (HOT) FPA has typical NE Delta T similar to 19 mK, J(D) similar to 6.2 x 10(-7) A/cm(2), and eta similar to 53% using 3-5 pm band pass filter at 115 K operating temperatures. Best performance 640 x 512 array format LWIR FPA has NE Delta T similar to 25 mK, J(D) similar to 2.5 x 10(-5) A/cm(2) and eta similar to 41% using 8-9.4 mu m band pass filter at 60 K operating temperatures. For MTF investigation, a novel direct one-to-one image approach of Line Spread function (LSF) and Edge Spread function (ESF) are patterned onto substrate-removed FPAs. The direct ISF and ESF image are produced by 1000 A degrees thick gold layer deposition. The direct image horizontal and vertical MTFs are compared with projected knife-edge ESF-derived MTFs and results indicate that direct image MTFs have higher values compared to projected knife-edge ESF-derived MTFs at a Nyquist frequency. However, direct image MIT requires no lens MTF correction. The only relevant requirement for the direct image MTF is for the deposited pattern and substrate to be extremely thinned in which the HOT-BIRD FPAs fulfilled for this investigation.
The modulation transfer function (MTF), when used with amplitude modulation (m(A)) data, is a vital coherent optical performance measure for a spatial light modulator (SLM). A new image plane amplitude MTF (MTFA) meas...
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The modulation transfer function (MTF), when used with amplitude modulation (m(A)) data, is a vital coherent optical performance measure for a spatial light modulator (SLM). A new image plane amplitude MTF (MTFA) measurement method is presented for electrically addressed SLMs. It involves digital analysis of the output image of a square-wave pattern written onto the SLM. modulation-level effects are also addressed. Optical laboratory results are presented for two liquid-crystal SLMs. The need to consider amplitude rather than intensity modulation (when coherent optical processing applications are considered) is noted in terms of SLM biasing. (C) 2001 Optical Society of America.
The modulation transfer function (MTF) of a pixelated liquid crystal spatial light modulator (LC-SLM) has been derived as a function of the fill factor. Based on the formula, we have investigated the dependence of the...
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The modulation transfer function (MTF) of a pixelated liquid crystal spatial light modulator (LC-SLM) has been derived as a function of the fill factor. Based on the formula, we have investigated the dependence of the MTF on the orientations and spatial frequency of the input patterns. Furthermore, we have proposed and demonstrated a method for improving the MTF of a LC-SLM. (C) 1999 Published by Elsevier Science B.V. All rights reserved.
A calculation program of the modulation transfer function (MTF) of a fish-eye lens is developed with the autocorrelation method, in which the sixth-order wave aberration theory of ultra-wide-angle optical systems is u...
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A calculation program of the modulation transfer function (MTF) of a fish-eye lens is developed with the autocorrelation method, in which the sixth-order wave aberration theory of ultra-wide-angle optical systems is used to simulate the wave aberration distribution at the exit pupil of the optical systems. The autocorrelation integral is processed with the Gauss - Legendre integral, and the magnification chromatic aberration is discussed to calculate polychromatic MTF. The MTF calculation results of a given example are then compared with those previously obtained based on the fourth-order wave aberration theory of plane-symmetrical optical systems and with those from the Zemax program. The study shows that MTF based on the sixth-order wave aberration theory has satisfactory calculation accuracy even for a fish-eye lens with a large acceptance aperture. And the impacts of different types of aberrations on the MTF of a fish-eye lens are analyzed. Finally, we apply the self-adaptive and normalized real-coded genetic algorithm and the MTF developed in the paper to optimize the Nikon F/2.8 fish-eye lens;consequently, the optimized system shows better MTF performances than those of the original design. (C) 2018 Optical Society of America
The modulation transfer function (MTF) is a standard method used for estimating the image quality of a component for detail recording in an image forming system and for printing quality of the final products. This stu...
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The modulation transfer function (MTF) is a standard method used for estimating the image quality of a component for detail recording in an image forming system and for printing quality of the final products. This study focused on the measurement of MTF of nonprinted and printed silk fabrics and a correlation of the MTF data to sharpness of the printed silk fabric using the in-house formulated ink jet ink. The MTF of the surface was measured using the sinusoidal test pattern in contact with the fabric using spatial frequencies from 0.375 to 3.0 cycles/mm. The sinusoidal test target scanned by a microdensitometer in the reflection density mode. These data comprise two frequencies;the high frequency is the characteristic of the fabric while the low frequency is the light scattering of the yams in contact with the sinusoidal target. The sinusoidal curves at the low frequency were used for further calculation of the MTF values. The result indicated that the measurement of MTF of silk fabric using the contact sinusoidal method can find the point spread function of silk fabrics. This research investigated the relationships of weave style and direction, wicking properties, and the MTF of four different silk fabrics with plain weave (silk A, C, and D) or twill weave (silk B). Dot gain by the Yule-Nielsen model was investigated. The coefficient d calculated by the MTF empirical model was 0.0604 and the coefficient n by the Yule-Nielsen model was 1.636 for silk D which had the lowest d and n coefficients compared with other silk fabrics, indicating good quality in terms of image sharpness. (c) 2007 Society for Imaging Science and Technology.
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