1. Forward operating current If:
It refers to the forward current value when the light-emitting diode emits light normally. In actual use, IF should be selected below 0.6IFm according to needs.
2. Forward operating voltage VF:
The operating voltage given in the parameter table is obtained under a given forward current. It is generally measured when IF=20mA. The forward operating voltage VF of the light-emitting diode is 1.4~3V. When the external temperature rises, VF will decrease.
3. V-I characteristics:
The relationship between the voltage and current of the light-emitting diode. When the forward voltage is less than a certain value (called the threshold), the current is extremely small and no light is emitted. When the voltage exceeds a certain value, the forward current increases rapidly with the voltage and emits light.
4. Luminous intensity IV:
The luminous intensity of the light-emitting diode usually refers to the luminous intensity in the direction of the normal line (for cylindrical light-emitting tubes, it refers to its axis). If the radiation intensity in this direction is (1/683) W/sr, the light is 1 candela (symbol: cd). Since the light-emitting diode intensity of a general LED is small, the luminous intensity is often measured in candela (mcd).
5. LED luminous angle:
-90- +90
6. Spectral half width:
It indicates the spectral purity of the light-emitting tube.
7. Half-value angle 1/2 and viewing angle:
The half-value angle 1/2 refers to the angle between the direction where the luminous intensity value is half of the axial intensity value and the luminous axis (normal direction).
8. Full form:
The angle calculated based on the LED luminous solid angle, also called the plane angle.
9. Viewing angle:
Refers to the maximum angle of LED luminescence. Depending on the viewing angle, the application is also different. It is also called the light intensity angle.
10. Half form:
The angle between the normal direction 0&փող; and the maximum luminous intensity value/2. Strictly speaking, it is the angle corresponding to the maximum luminous intensity value and the maximum luminous intensity value/2. The packaging technology of LED causes the maximum luminous angle to be not the light intensity value of the normal direction 0°, and the deviation angle is introduced, which refers to the angle between the angle corresponding to the maximum luminous intensity and the normal direction 0°.
11. Maximum forward DC current IFm:
The maximum forward DC current allowed. Exceeding this value may damage the diode.
12. Maximum reverse voltage VRm:
The maximum reverse voltage allowed is the breakdown voltage. Exceeding this value may cause the light-emitting diode to be damaged by breakdown.
13. Working environment topm:
The ambient temperature range in which the light-emitting diode can work normally. Below or above this temperature range, the light-emitting diode will not work normally and the efficiency will be greatly reduced.
14. Allowable power consumption Pm:
The maximum value of the product of the forward DC voltage allowed to be applied to the two ends of the LED and the current flowing through it. Exceeding this value will cause the LED to heat up and be damaged.