DEVELOPMENTS AND APPLICATIONS OF HIGH-PERFORMANCE CCD AND CMOS IMAGING ARRAYS

Abstract

For over 20 years, charge-coupled devices (CCDs) have dominated most digital imaging applications and markets. Today, complementary metal oxide semiconductor (CMOS) arrays are displacing CCDs in some applications, and this trend is expected to continue. Low cost, low power, on-chip system integration, and highspeed operation are unique features that have generated interest in CMOS arrays. This paper reviews current CCD and CMOS sensor developments and related applications. We compare fundamental performance parameters common to these technologies and describe why the CCD is considered a mature technology, whereas CMOS arrays have significant room for growth. The paper presents custom CMOS pixel designs and related fabrication processes that address performance deficiencies of the CCD in high-performance applications. We discuss areas of development for future CCD and CMOS imagers. The paper also briefly reviews hybrid imaging arrays that combine the advantages of CCD and CMOS, producing better sensors than either technology alone can provide.

Laser Induced Breakdown Spectroscopy

“…3, 2007 very useful for understanding the principles of operation of some devices used in LIBS instrumentation. [46][47][48][49][50][51][52][53][54] As a typical LIBS instrument is made up of well defined parts, including a laser source for sample ablation and excitation, an optical system for driving and collecting the laser and plasma radiations, a wavelength analyzer, and a detection system, the following sections will describe the instrumentation in this sequence, highlighting the technological advances of recent years. Two additional sections describe mobile instruments, due to the increasing interest in this area, and commercial instruments, which, after a premature commercialization in the 1960s and 1970s, have only recently become available again.…”

“…In a bi-dimensional configuration, they are also called CCD cameras. [46][47][48] The linear configurations (PDA or CCD) are very used in conjunction with conventional grating spectrographs while bi-dimensional CCD are especially employed with echelle spectrographs, due to the characteristic bidimensional dispersion generated by this kind of wavelength selector (see previous section). In one special exception, Yaroshchyk et al 156 used the bi-dimensional capability of a CCD camera in conjunction with a conventional grating spectrograph for the simultaneous detection of two plasma generated from liquid jets, one of them containing the analyte, by means of the partition of the detector into two linear detection regions.…”

First evidence of phase-contrast imaging with laboratory sources and active pixel sensors

“…Major advantages of CMOS with respect to CCDs were highlighted since their invention in the early 1990s [10]. These advantages include higher speed, lower cost and power consumption, true random access to individual pixels and, in particular, opportunity for built-in intelligence [11]. This last aspect is of particular significance in this context, as the ultimate aim would be to develop a sensor design with implemented functions capable of self-detecting the edge-enhanced structures typical of phase-contrast images with high speed.…”

Comparative Study of CCD & CMOS Sensors for Image Processing

“…Further digital-signal processing is used to perform white balancing and color correction as well as to diminish the adverse effects of faulty pixels and imperfect optics. Finally, the image is compressed and stored in memory [2]. Other processing and control operations are also included for performing auto-focus, auto-exposure, and general camera control.…”