- 31 July 2009
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το βρηκα στο σαιτ της Nexttorch
Method of measuring distance
We use the following formula to calculate distance:
E= I/d[SUP]2[/SUP]
E is illuminance in lux
I is luminous intensity in cd
d is distance in meters
As a standard practice, the illuminance E of the light is measured at 2 meters using a light meter. By manipulating the above formula, we can determine the luminous intensity I (I=E×2[SUP]2[/SUP]). We can also calculate the Direct Distance d where the light produces an illuminance of 0.25lux (d= (I/0.25)[SUP]1/2[/SUP]). Dividing the Direct Distance by 2, we get the Maximum Effective Distance.
Method of measuring distance
We use the following formula to calculate distance:
E= I/d[SUP]2[/SUP]
E is illuminance in lux
I is luminous intensity in cd
d is distance in meters
As a standard practice, the illuminance E of the light is measured at 2 meters using a light meter. By manipulating the above formula, we can determine the luminous intensity I (I=E×2[SUP]2[/SUP]). We can also calculate the Direct Distance d where the light produces an illuminance of 0.25lux (d= (I/0.25)[SUP]1/2[/SUP]). Dividing the Direct Distance by 2, we get the Maximum Effective Distance.