Imaging tubes

Infrared patterns can lead to detection of lack of bonding between surface platings, between coatings and base metal, or within bra2ed honeycombs and other composite materials where bonding is vital. Mote recent developments involve infrared television or image tubes similar to the types used for night vision in military and other appHcations. 

Optoelectronic components produced by CVD include semiconductor lasers, light-emitting diodes (LED), photodetectors, photovoltaic cells, imaging tubes, laser diodes, optical waveguides, Impact diodes, Gunn diodes, mixer diodes, varactors, photocathodes, and HEMT (high electron mobility transistor). Major applications are listed in Table 15.1.El... 

A typical streak camera image tube is shown in Fig. 17(a) (Hadland Photonics Ltd., Imacon). Briefly, its method of operation is as follows. The light signal strikes the photocathode and is converted with the associated focusing electrode beam. Until the camera is triggered, this beam is deflected onto the aperture slit by a constant potential on the shutter plates. When triggered, the voltage on the shutter plates drops to... 

Fig. 17. (a) Diagram of a streak camera imaging tube and (b) an image intensifier system for low light levels. 

The first detectors to be used in OMA systems were standard TV image tubes. These were silicon vidicons or the more sensitive Silicon Intensified Target (SIT) detectors, which both employed silicon targets to convert optical information into electronic form. More recently, the use of solid state detectors in the form of a diode array (Reticon) has been found to have some advantages over the vidicons and SIT tubes. Current developments in the field of charge coupled devices (CCD) will probably soon provide an even better multielement detector for use in OMA systems. 

Fig. 17. Structure of an SIT-imaging tube, with principle of the target...

OBJECTIVE LENS f 1 IMAGE TUBE TO POWER SUPPLY ... 

A simplified diagram of an IR viewer is shown in Figure 1. IR radiation is focused by the objective lens (typically a 35 mm camera lens) onto the cathode of the IR image tube. The cathode is a glass surface containing a semi transparent layer of materials (silver, oxygen and cesium) which discharge electrons in proportion to the amount of IR radiation... 

Furthermore, the IR tubes could not withstand the shock of repeated gun fire. Phosphor particles would dislodge from the image tube s florescent screen and settle on the lens electrodes causing internal flashing. 

IR Viewer / range 100 yards. Complete with optics,eyepiece,power supply battery pack,IR source and all necessary construction plans,instructions and parts sources. Plans- 8.00 High voltage power supply and all electronic parts- 44.50 Above assembled and tested- 59.50 Selected 6032 image tube- 16.00 Large 6" government 100 IR filter- 7.00. ... 

E. Lynn, MA 01904 Peabody, MA B F and Meshna sell unused RCA 6032 IR image tubes for 9 to 12 they also provide, with the tube, free instructions on how to construct a complete IR viewer for less than 100 in parts. Radio - Electronics, December, 1974, contains plans for building an IR viewer based on the 6032 tube.B F sells kits for constructing a viewer the kit contains the 6032 tube,objective lens,eyepiece, components of the power supply, and instructions. 

A second major advantage of photoemissive devices is the ease with which uniform, large-area detector surfaces can be fabricated. Such surfaces, while important for simple photomultipliers, are a prerequisite for successful imaging devices, including both direct-view intensifiers and image tubes with scanned electron beam readout [5.3]. 

CCDs and CMOSs are the detectors in virtually every digital ims Lng system. CCDs have also displaced the imaging tubes in television cameras. 

Color television s RGB system (Ernst Alexanderson) The RGB system uses three image tubes to scan scenes through colored filters and three electron guns in the picture tube to reconstruct scenes. 

Imaging tube properties The photosensitive layer and the beam spot size will affect maximum resolution. 

Rao, N.V. 1990. Development of high resolution camera tube for 2000 Hne TV system. SPIE, Electron Image Tubes and Image Intensifiers, vol. 1243, pp. 80-86. 

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