Foot lambert

Foot-Lambert X square foot Area = Lumen... 

Thus, we have two units of measurement of intensity. One is related to scattering from a surface, L, i.e.- in foot-lamberts and the other is related to emittance, H, i.e.- in lumens per square foot. Although we have assumed "white" light up to now, either of these two can be wavelength dependent. If either is wavelength dependent, then we have a pigment (reflective- but more properly called scattering) with intensity in foot-lamberts, or an emitter such as a lamp or phosphor (emittance) with intensity in lumens. 

W sr cm ). Photometric SI units are candela per square meter (cd m" -but foot-Lamberts, (Im sr" ft" ) are also commonly used terms. 

Figure 9 Radiance and luminance measurement. Abbreviation FI, foot Lamberts.

ISPD. The ISPD provides a linear dynamic range (1-32) of at least 16,384 1 Q4 bit A/D converter). At illumination levels above 4 x 10"5 foot candle (with a corresponding output brightness of approximately 1 foot lambert), the MCP saturates and thereafter has a non-linear transfer characteristic. However, this level is way above the A/D converter saturation level and has no implications on low light level spectroscopy. 

Although we have assumed "white" light up to now, either of these two can be wavelength dependent. If either is wavelength dependent, then we have a pigment (reflective- but more properly scattering) with intensity in foot-lamberts, or a phosphor (emittance) with intensity in lumens. 

Foot lambert n. Foot lambert is the unit of photometric brightness (luminance) equal to l/7tcandle/ft. ... 

Luminance is the light emitted or reflected from a surface per unit area. Luminance has units of foot lamberts. 

Foot Lambert n Foot lambert is the unit of photometric... 

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