Self-scanned Array Research Articles

A multichannel X-ray detector

A multichannel X-ray detector with a spatial resolution of 0.13 mm and a maximum of 200 effective channels is described. The detector consists of a conversion electrode to convert X-rays into electrons, a microchannelplate phosphor screen assembly to amplify the electron signal, a self-scanning array containing 1024 photodiodes and optics to form an image from the phosphor screen on the self-scanning array. A magnetic field is used to form an image of the electrons from the conversion electrode on the channelplate. The resolution of the detector is determined by the magnetic imaging system and the channelplate/phosphor-screen assembly.

Directional laser velocimetry without frequency biasing: part 2

In an earlier paper, Agrawal and McCullough demonstrated that a single laser beam focused at the point of measurement can be used to obtain both the magnitude and direction of local fluid velocity without the use of beam-splitting optics or frequency biasing devices. Additionally, the photoelectric signal was shown to be a zero-mean sine wave suitable for existing counter-type laser Doppler velocimeter signal processors. The method described in the above paper indicated the use of two offset photodetector arrays; the resulting photocurrents from the two arrays were correlated to give direction. In this paper we describe the implementation of the method using a self-scanning diode array. Detector sensitivity in the array is discussed and microchannel plate detectors are suggested for increased sensitivity.

Intensified Self-Scanned Array Technology Review

The purpose of this review is to describe the general status of the intensified self-scanned array technology area. Since the invention of CCDs in 1970, a wide variety of different types of self-scanned arrays (CCDs, CIDs, and photodiode arrays) have been used with photoelectronic imaging detectors to produce line-scan and TV raster-scan output signals for spectroscopic, facsimilie, low-light-level TV, and many other applications. Both optical input and electron-bombardment mode self-scanned array (SSA) readout methods have been employed. The advantages of using a photocathode as the prime detector, and microchannel plates for high-gain, are discussed. A major part of this review is to describe the various types of image tube intensified SSA cameras and instruments that have been made. Finally, some of the possibilities for new detector designs, based on the intensified SSA technology, are presented.

Noise in large-aperture self-scanned diode arrays

An equation for the random noise of self-scanned silicon photodiode arrays is developed which includes significant terms not previously considered. It is shown that, including these terms, the new 2.5-mm-high self-scanned arrays are only slightly noisier than older arrays; but because of their much greater aperture, they can detect much smaller light fluxes than the older arrays even when used with simple, inexpensive amplifiers.

Photodiode arrays — Characteristics and applications

The first part of this article is intended to provide an understanding of the factors affecting the performance and operation of linear detector arrays. It discusses the physical arrangements, operating principles, fixed-pattern noise and other parameters. Some of the applications for linear detector arrays in industry are also described. The second part of the article discusses two-dimensional self-scanned arrays, camera systems and their application in industry.

Optical self-scanned arrays. Part 1: Principles of self-scanned arrays

On 16th January 1979, the IERE Components and Circuits Group organized a one-day colloquium on Optical Self-Scanned Arrays at the Royal Institution, London. As an experiment in reporting colloquium proceedings, Professor Beynon who chaired the meeting, asked all the contributors subsequently to produce shortened versions of their oral presentations for editing into a symposium on this important subject.In publishing this article the efforts of Professor Alan Pugh are gratefully acknowledged. As chairman of the Components and Circuits Group, Professor Pugh undertook the organization ofthe colloquium and had hoped to chair the day's proceedings. He was prevented from doing so at the last moment by a national rail strike called for 16th January.

Optical self-scanned arrays. Part 4: Self-scanned pyroelectric arrays

Optical self-scanned arrays. Part 4: Self-scanned pyroelectric arrays

Optical self-scanned arrays. Part 5: Enhancement of the uniformity of response of self-scanned arrays

Optical self-scanned arrays. Part 5: Enhancement of the uniformity of response of self-scanned arrays

Optical self-scanned arrays. Part 2: Using arrays in instrumentation

Optical self-scanned arrays. Part 2: Using arrays in instrumentation

Optical self-scanned arrays. Part 6: Optimization of image sensors

Optical self-scanned arrays. Part 6: Optimization of image sensors

Optical self-scanned arrays. Part 8: A helmet-mounted sight using c.c.d. technology

Optical self-scanned arrays. Part 8: A helmet-mounted sight using c.c.d. technology

Optical self-scanned arrays. Part 7: An experimental solid-state film scanner

Optical self-scanned arrays. Part 7: An experimental solid-state film scanner

Optical self-scanned arrays. Part 3: Development of large areacharge-coupled image sensors

Optical self-scanned arrays. Part 3: Development of large areacharge-coupled image sensors

High Density CID Imagers

The fabrication and performance of large (16K, 60K, and 78K cells) high density CID self-scanned imager arrays is described. Array fabrication used overlapping electrodes of two levels of polysilicon or a first level of polysilicon and a second level of antimony tin oxide. Yield considerations and the special processing steps required to fabricate these large chips are examined. Quantum efficiency curves of these structures are compared.

High density CID imagers

The fabrication and performance of large (16K, 60K, and 78K cells) high density CID self-scanned imager arrays is described. Array fabrication used overlapping electrodes of two levels of polysilicon or a first level of polysilicon and a second level of antimony tin oxide. Yield considerations and the special processing steps required to fabricate these large chips are examined. Quantum efficiency curves of these structures are compared.

Single electron counting by self-scanning diode array in a Kron camera

A linear self-scanning array of 512 elements was exposed to photoelectron bombardment in a Kron camera tube. This is a demountable tube in which the photocathode and the electron focal plane can be separated by means of a special coin valve. The diode array was mounted in the electron optical focal plane. The video signal amplitude distributions were analyzed when the diode array was exposed to electrons between 30 keV and 35 keV. The distribution of the signals due to single electrons could be resolved from the distribution of signals when no photoelectrons were present. The impairment of the SNR due to the lack of perfect resolution of the distributions amounts to no more than the loss of a few percent of the photoelectrons. The result of these tests encourages the immediate application of the diode array Kron tube spectrography to high resolution spectroscopy of very faint objects.

Annealing procedure for self-scanned diode arrays

Annealing procedure for self-scanned diode arrays

Transparent metal oxide electrode CID imager

The use of metal oxide transparent conductive electrodes in a charge-injection device (CID) imaging array has resulted in a quantum efficiency of approximately 70 percent, uniform throughout the visible, with useful array response out to 3500 /spl Aring/. The advantages of using highly transparent metal oxide electrodes for the fabrication of frontside illuminated arrays is described. A new high density CID cell is described, which does not require any contact windows or diffused regions. This cell structure is simply composed of two crossed rows and column electrodes and is easily fabricated. Because no contacts are required, it can be reduced in size for large high density arrays. The results for a 32/spl times/32 self-scanned array are presented.

Transparent metal oxide electrode CID imager

The use of metal oxide transparent conductive electrodes in a charge-injection device (CID) imaging array has resulted in a quantum efficiency of approximately 70 percent, uniform throughout the visible, with useful array response out to 3500 A. The advantages of using highly transparent metal oxide electrodes for the fabrication of frontside illuminated arrays is described. A new high density CID cell is described, which does not require any contact windows or diffused regions. This cell structure is simply composed of two crossed rows and column electrodes and is easily fabricated. Because no contacts are required, it can be reduced in size for large high density arrays. The results for a 32 × 32 self-scanned array are presented.

Single Electron Recording by Self-Scanned Diode Arrays

A unique multichannel photoelectron counting system can be made by using self-scanning semiconductor arrays in the electron bombardment induced mode provided the SNR in the self-scanning arrays permits the detection of single electrons. To investigate this in an experimental program, self-scanning light sensitive diode arrays were subjected to electron bombardment. In one experiment, a radioactive source Ni(63) was used to show that the 128 element (Reticon RL128L) self-scanned linear diode arrays were responsive to electrons, and good agreement could be derived between the high energy portion of the incident and -measured fluxes. In another experiment using an electron accelerator and 42-keV electrons, clear resolution of the pulse distribution peaks was obtained due to single, double, and triple incidences of electrons. The relative heights of the observed peaks obeyed a Poisson distribution as expected for random electron incidence. The incorporation of this device into a photoelectronic tube will result in a self-scanned photoelectronic detector closely approaching the theoretical performance limit.