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Singapore regulations & registration

Inspection Photometer

An inspection photometer is the calibrated optical instrument VICOM uses to measure the Visible Light Transmission of vehicle glass during periodic inspection.

Photometers measure VLT by sending a calibrated light source through the glass and measuring the transmitted intensity. The reading is typically accurate to ±2% absolute.

VICOM photometers are calibrated against traceable standards. The measurement is taken at multiple points on each window and the lowest value typically used.

Quality workshops own their own photometers and measure VLT pre-release. Infratint includes the VLT measurement on the customer record so the driver has documentation if questioned.