Konica Minolta T-10A, Инструкция по эксплуатации

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55
[Conforms to DIN]
Since the brightness at the measurement plane is proportional to the cosine of the angle at which the light
is incident, the response of the receptor must also be proportional to the cosine of the incidence angle.
The graph above shows the cosine correction characteristics of Konica Minolta Illuminance Meters T-10.
The cosine error of T-10 are shown in the table right.
Class L A B C
f
2
(%) 1.5 1.5 3 6
f
2
can be calculated as follows.
In addition, f
2
(
θ
) is represented by the following equation.
f
2
=
0
180
f
2
( θ ) sin2 θ θ d
ʃ
85 π
f
2
（ θ ）=
Y(0) cos θ
Y（ θ ）
­1 100 （ ％ ）
Y (
θ
) : Signal output as a function of the angle of
incidence
θ
: Azimuth angle measured with respect to the
normal to the measuring plane or optical axis