LED, as a new type of lighting source, has many advantages such as high efficiency, energy-saving, and long lifespan, gradually replacing traditional lighting sources. However, how can we ensure the light quality and efficiency of LED lights when purchasing them? This requires LED distribution testing and glare rating testing. This article will explore the application of LM-79 Type C Goniophotometer for LED testing.
The LM-79 Type C Goniophotometer working principle :
The LM-79 Type C Goniophotometer is mainly used for measuring the photometric performance of lamps and light sources, including the spatial distribution and color measurement of the lamps and light sources in different directions. The spectrophotometric method is used to qualitatively and quantitatively analyze the substance by measuring the absorption of light by the tested material at specific wavelengths or within a certain range of wavelengths. If there is a need to test parameters such as the IES file and the intensity distribution, it is recommended to use a distributed photometer system. With the continuous development of the photometer industry, an increasing number of companies and industries have started to use photometers, and many companies have entered and developed in the field of photometers.

LED distribution testing is a method used to evaluate the light quality and performance of LED light sources, fixtures, or modules. Through this testing method, we can obtain various data such as light distribution, light power, and light efficiency of LED light sources and lighting devices, thus evaluating their light quality and brightness. Generally speaking, the luminous intensity curve of LED fixtures should meet certain standards, such as beam angle, uniformity, and illuminance. By using the LM-79 Type C Goniophotometer for testing, we can accurately measure the light distribution and light power of LED light sources at different angles.
For LED fixtures, the beam angle is a very important parameter. It determines the range and brightness of the LED light source. Through photometric testing, we can obtain the specific numerical value of the beam angle, thus determining whether the LED fixtures meet our requirements. In addition, uniformity is alsoan important parameter to consider. Through photometric testing, we can obtain the luminous intensity curve and determine whether the uniformity of the LED light source meets the standard requirements. The uniformity of the light distribution is one of the important indicators to measure the lighting effect of a light source. If the uniformity is poor, there will be obvious brightness differences during the lighting process, affecting the usage effect.
Another parameter to pay attention to is the illuminance. Through photometric testing, we can obtain the illuminance values of LED light sources at different angles. This can help us understand whether the brightness of the LED fixtures meets the requirements for use. Glare is also an important issue to consider in the field of lighting. Excessive glare can cause discomfort or even harm to the eyes. Therefore, it is very important to use the LM-79 Type C Goniophotometer to test the glare rating. Through this test, we can determine the glare rating of LED fixtures and whether they meet the standard requirements.
During LED distribution testing and glare rating testing, we need to use professional instruments and equipment. The LM-79 Type C Goniophotometer is widely used for testing LED light sources, as it can accurately measure the light distribution and light power of LED light sources at different angles. This instrument usesthe distributed photometry method for measurement, with high accuracy and reliability.
When using the LM-79 for measuring LED light sources, the photometer needs to be placed in a fixed position, and the angle of the light source and the instrument needs to be controlled to obtain the illuminance data. During the testing, care should be taken to avoid direct irradiation of the photometer’s receiving port by the light source to avoid errors. In addition, certain controls should be made on the testing environment to ensure the accuracy of the test results. For example, it is necessary to ensure that the ambient light in the testing place does not affect the test results, and to avoid interference factors such as reflective light and scattered light during the testing.
In practical applications, the LM-79 Type C Goniophotometer is widely used in the research and development, production, and quality control processes of LED lighting products. By conducting distribution testing and glare rating testing on LED light sources, the light quality and performance of LED fixtures can be ensured, thereby improving the quality and competitiveness of the products.
It should be noted that using the LM-79 Type C Goniophotometer for testing can only obtain the light distribution and light power parameters of LED light sources under static conditions. In actual use, the lighting effect of LED fixtures maybe influenced by other factors such as temperature, humidity, and ambient light. Therefore, when using LED fixtures in practical applications, these factors should also be taken into consideration, along with factors such as light quality, brightness, and power consumption.
In conclusion, LED distribution testing and glare rating testing are important means to ensure the light quality and performance of LED fixtures. Using the LM-79 Type C Goniophotometer for testing can accurately measure the light distribution and light power parameters of LED light sources at different angles. This provides a scientific basis for the research and development, production, and quality control of LED products. When selecting LED fixtures, we can refer to relevant test reports and choose products that meet the requirements to ensure lighting effect and visual comfort. At the same time, with the development and application of LED technology, we believe that LED distribution testing and glare rating testing will receive more attention and contribute to the development of the LED lighting industry.
What is the definition of type C goniophotometer?
LSG-6000 Moving Detector Goniophotometer (Mirror Type C) was manufactured by LISUN completely meets LM-79-19, IES LM-80-08, COMMISSION DELEGATED REGULATION (EU) 2019/2015, CIE-121, CIE S025, SASO 2902, IS16106 and EN13032-1 clause 6.1.1.3 type 4 requirements. LSG-6000 is the latest upgraded product of LSG-5000 and LSG-3000 in compliance with the requirements of the LM-79-19 standard Clause 7.3.1, its an automatic light distribution intensity 3D curve testing system for measuring light. The darkroom can be designed according to the customer’s existing room size.
LM-79 Moving Detector Goniophotometer (Mirror Type C) 
Lisun Instruments Limited was found by LISUN GROUP in 2003. LISUN quality system has been strictly certified by ISO9001:2015. As a CIE Membership, LISUN products are designed based on CIE, IEC and other international or national standards. All products passed CE certificate and authenticated by the third party lab.
Our main products are Goniophotometer, Integrating Sphere, Spectroradiometer, Surge Generator, ESD Simulator Guns, EMI Receiver, EMC Test Equipment, Electrical Safety Tester, Environmental Chamber, Temperature Chamber, Climate Chamber, Thermal Chamber, Salt Spray Test, Dust Test Chamber, Waterproof Test, RoHS Test (EDXRF), Glow Wire Test and Needle Flame Test.
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