Infrared camera infrared light quality identification
May 02, 2024
A. The distinction between positive core and loose core
Whether the wick is used with a positive core or a bulk core determines the quality of infrared lamps, the price between the two is also very different, and even a difference of more than five times, which is an important reason for the price of infrared lamps in the market such as 369 and 1989. The camera is most sensitive to the luminescence spectrum at 850 nanometers of the lamp, that is, a red burst infrared tube. The infrared tube of this band is also the most expensive. Remove the lamp plate of the infrared lamp and find an adjustable power supply. In the dark environment, the output voltage of the regulated power supply is first adjusted to the rated working voltage of the infrared lamp, and the infrared lamp is connected. At this time, the infrared lamp works normally, and then the voltage is gradually lowered until the lamp tube goes out and the lamp is turned off. The degree of luminosity is the same. If all the lamps on the lamp panel are illuminated during this process, then the lamp is using a positive core; if there are any lamps that are slightly bright and the lamps are slightly darker, then the quality of the wick makes people doubtful. . There is also another method - measurement. The operating voltage of each lamp is measured while the infrared lamp is operating normally. Most LED infrared lamps currently on the market use low-power lamps. The chips are mostly 12MIL or 14MIL [mil = 0.0254 millimeters (mm)]. The normal working voltage of each lamp is about 1.5V. . With a digital multimeter, range switch to 2V file, measuring the working voltage of each lamp, if the positive core tube, the error value of the working voltage of each lamp within 0.03V, if greater than this value, especially the general comparison When it was large, it indicated that the lamps were not positive. This method is also suitable for 940 nm infrared lamps.
The advantages of a positive core tube are that it works stably. When it is new, it is as new as it is. It is as old as it used to be. After working for 35 years, the lamps on the lamp panel are seen again. They are very consistent. If the suspicion is low, proper adjustment of the operating current can make it rejuvenate. Dispersing the lamp is not the same. After six months of operation, some lamps on the lamp board are dark and there is no failure within one year. Even if you replace the bad pipe, it will still fail after a long time, because the overall quality is too bad.
Second, the size of the wick chip size
The formal method is to measure the size of the wick after dissolving the colloid with a chemical solvent. But for most people, even if you can dissolve the colloids, you cannot measure accurate data because we don't have a very accurate measurement tool [1 mil = 0.0254 mm]. It is usually to see the operating current. In general, the maximum operating current for a 12 MIL lamp is no more than 60 mA, and no more than 70 mA for 14 MIL. However, due to the market and other factors, some of the all-in-one 12MIL lamps have 80 mA operating current. This method is not sure. But we can provide a reference, that is, the operating current of the chip may be large, but the current is too short life. For example, the operating current of a lamp of 12MIL is 80 mA, and its lifetime is at most 2 years. You know this, you can have more plates on hand. Anyway, if you buy a lamp for one time, you have to make a profit for sales and engineering. Everyone is happy.
Third, look at the process
Watching craft is like looking at a person. If a person is dressed in a mess, it is difficult to inform him that his work will be serious (except for Mr. Chen Jingrun, of course). The quality of the process, to a certain extent, explains the quality of the product, especially the welding process. The lamp welding time requirement is less than 1.5 seconds. Too long welding time will directly affect the lamp life. This point we have been identified during the trial.
Fourth, other aspects
Look at the stability of infrared lamps from the working voltage. Observing the light board carefully, we can easily find that several light tubes on the light board are connected in series, and then these several groups are connected in parallel to form the entire light board circuit. If there is a problem with one of the lamps in each group of lamps, the group of lamps will be off. Most of the current lamp on the market has a working voltage of 12V and some are 24V. The 12V lamp is mostly a group of 6 to 7 lamps connected in series, and 24V is 14 or 15 are connected in series. It is also a faulty lamp. The number of inactive lamps with high voltage is much larger than that of low voltage lamp. That is, the lamp with a low operating voltage has a higher stability.
The quality of infrared lamps depends mainly on two aspects, in addition to the LED infrared diode is the power supply. The vast majority of infrared lamps are installed in high places. Once a problem arises, the contractor first picks up the trouble, and then the contractor finds the seller and the seller finds the manufacturer again; the profit of the seller is low, and the goods are picked up and sent back and forth. The last light may not necessarily make money and may lose money. So the quality of power is very important!
Five, on the array of infrared light
Array infrared light is actually a number of infrared LED chip on a substrate, the internal lines and ordinary LED infrared lights. Array infrared lamps must pay attention to the cooling measures. The back of the good-quality array infrared lamp has a thick heat sink, and thermal grease is also coated between the array substrate and the heat sink to facilitate heat dissipation.
Array-type infrared lamps have the advantages of small size and light weight, but they also have their shortcomings. Because they are also connected in series after the first parallel line, once a chip is damaged will result in a group of lights do not work, and can not replace this damaged chip. If the number of damaged groups is large, the entire substrate must be replaced, and the maintenance cost is relatively high.
Sixth, on the high-power infrared light
High-power infrared light (piranha package) is the most important thing is to heat, light board with aluminum substrate, and through the screw connection with the chassis, through the shell heat. In addition, many built-in fans, through the forced air cooling to increase the heat exchange between the lamp and the shell. If you use an ordinary circuit board, you can conclude that the quality of this light board is certainly not high, and the life expectancy is certainly not long.
Seven, on the life of infrared lamps
Manufacturers generally have a nominal life of 25,000 hours. The actual life is related to the lamp's production process, circuit design, power quality, and work environment.
