Application Notes—Photoconductive Cells
APPLICATION NOTE #1
Light - Some Physical Basics
Light is produced by the release of energy from the atoms of a material
when they are excited by heat, chemical reaction or other means. Light
travels through space in the form of an electromagnetic wave.
A consequence of this wave-like nature is that each “color” can be
completely defined by specifying its unique wavelength. The
400
Ultraviolet
(To X-rays and Gamma Rays)
Violet
Visible Light
wavelength is defined as the distance a wave travels in one cycle.
Since the wavelengths of light are very short they are normally
measured in nanometers, one nanometer being equal to 1 x 10
-9
meters.
The spectral response of PerkinElmer’s photoconductors are specified
by lots of relative response versus wavelength (color) for various
material types.
700
Infrared
(To Radar Waves)
Red
Wavelength
Violet
Blue
Green
Yellow
Orange
Red
Below 450 nm
450 - 500 nm
500 - 570 nm
570 - 590 nm
590 - 610 nm
610 - 700 nm
Natural Illuminance
Sky Condition
Direct Sunlight
Overcast Day
Twilight
Full Moon
Clear Night Sky (moonless)
Light Level (Typical)
10000 fc
1000 fc
1 fc
0.1 fc
0.001 fc
Lighting Condition
Candle - Lit Room
Auditorium
Classroom
Inspection Station
Hospital Operating Room
Room Illumination
Light Level (Typical)
5 fc
10 fc
30 fc
250 fc
500 - 1000 fc
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PERKINELMER [ PERKINELMER OPTOELECTRONICS ]
