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智能型高速CCD相机的时序电路的研制 总被引:3,自引:0,他引:3
首先详细地介绍了几种传统时序电路的实现方法与各自存在的优缺点 ,然后对 isp L SI器件的性能特点以及 TDI- CCD相机的组成结构、工作原理进行了简要地阐述 ,最后对采用 isp L SI器件实现 CCD相机时序电路的全过程进行了全面、细致地分析。本文结合实际课题 ,已由在线可编程大规模逻辑器件实现了高速 TDI- CCD相机的时序电路。此相机系统具有一些重要参数 (行周期、TDI级数、视频信号的增益、偏置参数 ) ,并可以灵活控制。同时该系统又具有高可靠性、高稳定性、低功耗等特点。 相似文献
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Performance of a time delay and integration (TDI) imager is analogous to a drum/periphery camera. Coupled to a modulated line generating laser diode, it is possible to use a TDI imager to encode the shape profile of a rotating cylindrical object as deformed gratings in a digital image. Among the various methods for extracting the phase from a deformed grating, the spatial phase detection (SPD) method is fast and easy to use. Errors are introduced in this method if the phase gradient is high over a grating interval. Here we propose a method to reduce the phase gradient by using a TDI feature which makes it possible to record images at variable lateral magnification. 相似文献
15.
Hongxin Ren Bohao Yu Yiping Du 《International Journal of Polymer Analysis and Characterization》2018,23(1):9-17
The main goal of this work is to identify polyurethane (PU) building blocks by pyrolysis gas chromatography/mass spectrometry (Py–GC/MS) and matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS). Toluene diisocyanate (TDI) and diphenylmethane diisocyanate (MDI) are widely used polymer building blocks. Py–GC/MS and MALDI-TOF MS were proved to be powerful methods to distinguish TDI-PU and MDI-PU according to the characteristic pyrolysis products and the different repeated units, respectively. In Py–GC/MS, the specific pyrolyzates are TDI for TDI-PU and MDI for MDI-PU. In MALDI-TOF MS, the weights of repeated units are 264?g/mol for TDI-PU and 340?g/mol for MDI-PU. 相似文献
16.
Tianhong Zhang Morton H. Litt Charles E. Rogers 《Journal of polymer science. Part A, Polymer chemistry》1994,32(8):1531-1537
Eight poly(urethane-sulfone)s were synthesized from two sulfone-containing diols, 1,3-bis(3-hydroxypropylsulfonyl)propane (Diol-333) and 1,4-bis(3-hydroxypropylsulfonyl)butane (Diol-343), and three diisocyanates, 1,6-hexamethylene diisocyanate (HMDI), 4,4′-diphenylmethane diisocyanate (MDI), and tolylene diisocyanate (TDI, 2,4- 80%; 2,6-20%). As a comparison, eight polyurethanes were also synthesized from two alkanediols, 1,9-nonanediol and 1,10-decanediol, and three diisocyanates. Diol-333 and Diol-343 were prepared by the addition of 1,3-propanedithiol or 1,4-butanedithiol to allyl alcohol and subsequent oxidation of the resulting sulfide-containing diols. The homopoly(urethanesulfone)s from HMDI and MDI are semicrystalline, and are soluble in m-cresol and hot DMF, DMAC, and DMSO. The copoly(urethane-sulfone)s from a 1/1 molar ratio mixture of Diol-333 and Diol-343 with HMDI or MDI have lower crystallinity and better solubility than the corresponding homopoly(urethane-sulfone)s. The poly(urethane-sulfone)s from TDI are amorphous, and are readily soluble in m-cresol, DMF, DMAC, and DMSO at room temperature. Differential scanning calorimetry data showed that poly(urethane-sulfone)s have higher glass transition temperatures and melting points than the corresponding polyurethanes without sulfone groups. The rise in glass transition temperature is 20–25°C while the rise in melting temperature is 46–71°C. © 1994 John Wiley & Sons, Inc. 相似文献
17.
For over 27 years, SCD has been manufacturing and developing a wide range of high performance infrared detectors, designed
to operate in either the mid-wave (MWIR) or the long-wave (LWIR) atmospheric windows. These detectors have been integrated
successfully into many different types of system including missile seekers, time delay integration scanning systems, hand-held
cameras, missile warning systems and many others. SCD’s technology for the MWIR wavelength range is based on its well established
2D arrays of InSb photodiodes. The arrays are flip-chip bonded to SCD’s analogue or digital signal processors, all of which
have been designed in-house. The 2D focal plane array (FPA) detectors have a format of 320×256 elements for a 30-μm pitch
and 480×384 or 640×512 elements for a 20-μm pitch. Typical operating temperatures are around 77–85 K. Five years ago SCD began
to develop a new generation of MWIR detectors based on the epitaxial growth of antimonide based compound semiconductors (ABCS).
This ABCS technology allows band-gap engineering of the detection material which enables higher operating temperatures and
multi-spectral detection. This year SCD presented its first prototype FPA from this program, an InAlSb based detector operating
at a temperature of 100 K. By the end of this year SCD will introduce the first prototype MWIR detector with a 640×512 element
format and a pitch of 15 μm. For the LWIR wavelength range SCD manufactures both linear Hg1−xCdxTe (MCT) detectors with a line of 250 elements and time delay and integration (TDI) detectors with formats of 288×4 and 480×6.
Recently, SCD has demonstrated its first prototype uncooled detector which is based on VOx technology and which has a format of 384×288 elements, a pitch of 25 μm, and a typical NETD of 50 mK at F/1. In this paper,
we describe the present technologies and products of SCD and the future evolution of our detectors for the MWIR and LWIR detection.
The paper presented there appears in Infrared Photoelectronics, edited by Antoni Rogalski, Eustace L. Dereniak, Fiodor F. Sizov, Proc. SPIE Vol. 5957, 59570S (2005). 相似文献
18.
阴极电泳涂料的制备及MEQ值的测定 总被引:1,自引:0,他引:1
采用封闭的甲苯二异氰酸酯作为固化剂合成了环氧树脂阴极电泳涂料,讨论了基料树脂的合成条件,最终确定了合成树脂的反应条件为:温度80℃,反应时间为2h,并采用了简便的方法测定了槽液的MEQ值,在150v下电泳3min,得到外观平整,综合性能优良的漆膜. 相似文献
19.
四氢呋喃聚合向丁二酸酐链转移的研究栗方星,马克勤,陈琰,文佳,霍玉杰(南开大学化学系,天津,300071)(天津安普公司,天津)关键词THF,TDI,CH_3COSbCl_6,表观聚合速率常数在THF阳离子聚合的过程中,活性中心向丁二酸酐链转移[1]可... 相似文献
20.
W. R. Pulleyblank 《Operations Research Letters》1981,1(1):28-30
Schrijver has shown that any rational polyhedron is the solution set of a unique minimal integer TDI linear system. We characterize this system for the case of b-matchings, one of the few known cases for which such a system is strictly larger than a minimal linear system sufficient to define the polyhedron. 相似文献