070 am
A, Pin
040 0.45 050 055 ago
5.1. Photometry and Geometrical Optics
- Spectral response of an eye V 00 is shown in Fig. 5.1.
V
1.0
0.8
0.5
0.4
a2
Fig. 5.1.
A=1.5melm
far ii..-0.555,um
PART FIVE. OPTICS
- Luminous intensity I and illuminance E:
dcto. 71C
dC2 ' dS •
- Illuminance produced by a point isotropic source:
I cos a
E — r 2
where a is the angle between the normal to the surface and the direction to the
source.
- Luminosity M and luminance L:
= del )^ emit^ L— clil
M dS , dt1 AS cose • (5.1c)
- For a Lambert source L = const and luminosity
M = aL. (5.1d)
(5.1a)
(5.1b)
