MFDigital CD DVD Information Library: CD Manufacturing > Quality Assurance

MFDigital CD DVD Information Library

Thursday, June 24, 2004

CD Manufacturing > Quality Assurance > Mechanicals Tests

Mechanical Tests

Mechanical Tests and measurements include:

Radial Noise to determine the lateral tracking drift from the center of the pits being scanned.
Eccentricity calculates the accuracy of the center hole.
BLER is the Block Error Rate before any error correction take place.
E22 measures uncorrected errors correctable by error concealment.
E32 is a measure of uncorrectable errors and should be zero.
Track Pitch which should be between 1.5 to 1.7 microns.
Scan velocity which should be between 1.2 and 1.4 m/s.
BLI (begin of lead-in) should be at a maximum radius of 23 mm.
BPL (begin of program area), should be at radius 24.8mm to 25mm.
BLO (begin of lead-out) must not exceed radius 58.

These measurements are made at the same time as the electrical signals are measured.

- posted by J @ 7:31 AM

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