CCD Technology

Abstract

Charge-coupled devices (CCDs) continue to reign supreme in the realm of imaging out to 1 μm, with the steady improvement of performance and the introduction of innovative features. This review is a survey of recent developments in the technology and the current limits on performance. Device packaging for large, tiled focal-plane arrays is also described. Comparisons between CCDs and the emerging CMOS imagers are highlighted in terms of process technology and performance.

Novel Software-Based Method to Widen Dynamic Range of CCD Sensor Images

“…CCD sensor has reigned supreme in the realm of imaging with the steady improvement of performance, especially on scientific area [5] due to its advantage of high quantum efficiency. The QE which is defined as the number of signal electrons created per incident photon is one of the most important parameters used to evaluate the quality of a detector which affects the DR and SNR of captured images.…”

“…By having bigger bucket more rain drops, number of photons, is collected, which can be seen as increase of the spatial quantum efficiency [10] resulting in DR quality improvement of captured images. The temporal quantum efficiency is related to accumulation of photoelectrons during the exposure time and is regulated by the fill factor [5]. The quantum efficiency is affected by fill factor as in = × , where is the effective and is the fill factor which is the ratio of light sensitive area versus total area of a pixel [5].…”

“…The temporal quantum efficiency is related to accumulation of photoelectrons during the exposure time and is regulated by the fill factor [5]. The quantum efficiency is affected by fill factor as in = × , where is the effective and is the fill factor which is the ratio of light sensitive area versus total area of a pixel [5]. A typical dynamic range, the ratio of the brightest accurately detectable signal to the faintest, of CCD sensors is proportional to the number of detected photons.…”

“…Over the past twenty years, the quality of digital camera sensors has made tremendous progress, especially in increasing resolution and improving low-light performance [4]. This has been achieved by reducing the pixel size and improving the quantum efficiency (QE) of the sensor [4,5]. Assuming each pixel corresponding to one cone in fovea, the pixel density in camera sensor should be close to 199,000 /mm2 which is the average density of the peak fovea cones in human eyes [2].…”

Photon imaging using post-processed CMOS chips

“…However, Canon Inc. has recently announced a 202 × 205 mm 2 CMOS imaging array, this single device just ts onto a 12 ′′ wafer [1]. Larger detector areas can be made by tiling elements [2]. A good example of a very large tiled detector array is shown in g. 1.1.…”