Our evaluation machines are from RTI. You can visit the RTI website here.
Take an interactive Flash tour of the whole process here.
Think CVA for videotape recycling.
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Tape 'erase and evaluation'
process
An introduction to magnetic tape surface defect detection
This process works on Digital Betacam (DigiBeta), Betacam, DVCam, DVCPro, HDCam, HDV, DVCPro 50 and Umatics.
The defect detection and evaluation works by reading the modulation of specular light that is reflected off the tape.
The tape is lowered into position in a cassette tray, where sensors detect what type of tape it is and its size. The lacing mechanism feeds the tape around the various rollers and guides, and across the main detector sensor.
The sensor is set up to react to reflected light from a specially filtered consistent light source. In fact, there are six light sensors which overlap slightly so as to cover the entire tape width.
The detectors are voltage sensitive and are individually biased on a known and perfect control tape. These control voltages form the heart of the referencing and sensitivity settings which can be pre-programmed into the evaluator machine for different customer requirements (eg: only report defects after one minute in, only report major defects, report all defects etc.)
Any defects found will alter the light and the sensors will initially respond to the voltage variation. This information is converted to represent the type of defect found, eg: crease, drop out or scratch.
Meanwhile, the tape runs across two burnishing blades and three sets of cleaning tissues which take off excess oxide to prevent head clogging.
After evaluation, the tape is rewound into the cassette and the tape is ejected. A list of all defects, if any, and their location on the tape, is printed and placed into the relevant cassette box.
Optical evaluation has been popular in the industry for the last ten years.
If you want to understand more about the science behind our process, why not take our interactive Flash tour?
An introduction to magnetic tape surface defect detection
This process works on Digital Betacam (DigiBeta), Betacam, DVCam, DVCPro, HDCam, HDV, DVCPro 50 and Umatics.
The defect detection and evaluation works by reading the modulation of specular light that is reflected off the tape.
The tape is lowered into position in a cassette tray, where sensors detect what type of tape it is and its size. The lacing mechanism feeds the tape around the various rollers and guides, and across the main detector sensor.
The sensor is set up to react to reflected light from a specially filtered consistent light source. In fact, there are six light sensors which overlap slightly so as to cover the entire tape width.
The detectors are voltage sensitive and are individually biased on a known and perfect control tape. These control voltages form the heart of the referencing and sensitivity settings which can be pre-programmed into the evaluator machine for different customer requirements (eg: only report defects after one minute in, only report major defects, report all defects etc.)
Any defects found will alter the light and the sensors will initially respond to the voltage variation. This information is converted to represent the type of defect found, eg: crease, drop out or scratch.
Meanwhile, the tape runs across two burnishing blades and three sets of cleaning tissues which take off excess oxide to prevent head clogging.
After evaluation, the tape is rewound into the cassette and the tape is ejected. A list of all defects, if any, and their location on the tape, is printed and placed into the relevant cassette box.
Optical evaluation has been popular in the industry for the last ten years.
If you want to understand more about the science behind our process, why not take our interactive Flash tour?