Background > Light transmittance

The light transmittance is computed according to the following equation (DIN 67 504):

The values of the product S*V of the relative spectral distribution of the light source (here: D65) and the spectral luminous efficiency are these:

They are taken from the following table (also from DIN 67504):

Wavelength [nm] S*V

380 0.0000

390 0.0005

400 0.0030

410 0.0103

420 0.0352

430 0.0948

440 0.2274

450 0.4192

460 0.6663

470 0.9850

480 1.5189

490 2.1336

500 3.3491

510 5.1393

520 7.0523

530 8.7990

540 9.4427

550 9.8077

560 9.4306

570 8.6891

580 7.8994

590 6.3306

600 5.3542

610 4.2491

620 3.1502

630 2.0812

640 1.3810

650 0.8070

660 0.4612

670 0.2485

680 0.1255

690 0.0536

700 0.0276

710 0.0146

720 0.0057

730 0.0035

740 0.0021

750 0.0008

760 0.0001

770 0.0000

780 0.0000

For other illuminants than D65 the product S*V is divided by the intensity of the D65 light source and multipied by the intensity of the chosen illuminant.