The important parameters
1, positive If working current
It refers to the light-emitting diodes normal glowing positive current value. In be used actually shall be according to the need to select the IF below 0.6 · IFm.
2, positive working voltage VF
Parameters of the working voltage is given in the table at a given positive electrical flow. Is usually measured during the IF = 20 ma. Light emitting diodes are working voltage VF in 1.4 ~ 3 v. At higher temperatures in the world and the VF will decline. 
3, V - I characteristic
Light-emitting diodes of the relationship between voltage and current in the forward voltage is less than a certain value (called threshold), small current, light. When the voltage exceeds a certain value, after the forward current voltage increase rapidly, glow.
4, luminous intensity IV
The luminous intensity of light-emitting diodes, often referred to as normal () refers to the axis of cylindrical luminous tubes direction of luminous intensity. If the radiation intensity in the direction of (1/683) W/sr, glow, 1 candela (symbol for CD). As a result of the general LED light-emitting diodes, intensity is small, so the luminous intensity commonly used candles (candela, MCD) as a unit.
5, the LED light Angle
- 90 ° - + 90 °
6 and a half, spectral width Δ lambda
It said light-emitting tube spectral purity.
7 1/2 and perspective, half value Angle theta
Theta 1/2 refers to half of the axial intensity is a luminous intensity value direction and Angle of optical axis to the (normal).
8, the whole shape
According to the LED solid Angle conversion from point of view, also called plane Angle.
9 and perspective
Refers to the maximum Angle of LED, according to the Angle of view is different, have different application, also called Angle of light intensity.
10 and a half
Method to 0 ° and the Angle between the maximum luminous intensity / 2. Strictly speaking, is the maximum luminous intensity and maximum luminous intensity / 2 corresponding Angle. LED packaging technology, leading to the biggest light Angle is not normal light intensity value of 0 °, introducing the deviation Angle, referring to is the luminous intensity corresponding to the Angle of the largest and the method to the Angle between 0 °.
11, maximum positive IFm dc current
Allowed to add one of the biggest positive dc current. More than this value can damage the diodes.
12, the largest reverse voltage VRm
The biggest reverse voltage is allowed to add the breakdown voltage. More than this value, light-emitting diodes can be broken down.
13 topm, work environment
Light-emitting diodes working environment temperature range. Below or above this temperature range, light-emitting diodes will not work properly, the efficiency is greatly reduced.
14 and allow power Pm
Allowed to add to the LED on both ends of the positive dc voltage and current flow through the maximum value of product. More than this value, LED fever, damage.
Characteristics of the led
(1) four yuan chip, using the MOVPE process preparation, brightness relative to the conventional chips light.
(2) good reliability.
(3) is used widely.
(4) high safety.
(5) the long service life.