CCD-Camera

If the inspection equipment can be run under stable and reproducable conditions due to the QAP the basis for using a camera system for flaw detection is given.The camera system consists of CCD-cameras and a pattern recognition software. Up to four CCD-cameras can be served by one PC. One shot of the part may be copied up to 16 times in the computer and this theoretically enables the crack determination with 16 different parameter sets. 

A CCD camera and the PC are used to process the different null displacement rings whereby the movements can be followed trough in real time, and also very accurately measured. 

A CCD camera is located in the II(t, ) plane. It records the first speekle pattern and proeesses it digitally. After this, the diffuser G is rotated and trtinslated (Figure I). 

Shaw S L, Salmon E D and Quatrano R S 1995 Digital photography for the light microscope results with a gated, video-rate CCD camera and NIFI-image software BioTechniques 19 946-55... 

Theory and Equipment. Many diseases of the human body can be identified by visual appearance. Tumors in the upper gastrointestinal (GI) tract, for example, possess a characteristic salmon pink color (3). The presence of such a color can be an indication of disease. Endoscopy is the medical imaging tool used to detect such colors in the inside of hoUow internal organs such as the rectum, urethra, urinary bladder, stomach, colon, etc. An endoscope is the instmment used to perform endoscopy. Endoscopic imaging involves the production of a tme color picture of the inside of the human body using lenses and either hoUow pipes, a fiber optic bundle, or a smaU CCD camera. AU three use a large field-of-view, sometimes referred to as a fish eye, lens to aUow a 180° field of view. 

Endoscopes containing a CCD camera replace the fiber optic bundle with a smaU monochrome CCD chip at the focal point of the fish eye lens (4). 

CCD Camera. For standard CCD cameras a double-channel plate (amplification >10 ) is necessary. For high-sensitivity cameras (sensitivity >10 lux, cooled or with internal amplification) a single channel plate suffices. By controlling the channel plate high-voltage, i. e. amplification, a high dynamic range can be achieved with this system [3.50]. 

For detection of secondary ions a laterally resolving detector is necessary. In the first step a channel plate for amplification is used secondary electrons from the output of this device are accelerated either to a fluorescent screen or to a resistive anode. If a fluorescent screen is used the image is picked up by a CCD camera and summed frame by frame by use of a computer. The principal advantage of this system is unlimited secondary ion intensities, but compared with the digital detection of the resistive anode encoder the lateral and intensity linearity is not as well-defined. 

Fig. 14. Field emission patters from (a) closed-tip and (b) open-tip MWCNTs taken by a CCD camera [46],...

Safety Considerations. High-power lasers raise a number of safety issues. There are the flammability and the toxicity of dye solutions. Most importantly, the eye hazards of laser radiation require careful shielding of the beam, and interlocks that restrict access to the laser room and to the dome. The laser could also dazzle aircraft pilots if they look directly down the beam. It is therefore necessary to close a shutter in the beam when a plane comes too close, either manually by human spotters, or automatically by use of radar, thermal IR or CCD cameras. Care must also be taken to avoid hitting overhead satellites in the case of pulsed or high power laser systems. 

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