Comparing Thorlabs and Newport Integrating Spheres for Photometric Measurements

With the development of technology, LED lighting has been widely used in the field of illumination. In order to ensure the quality and performance of LED lighting, it is necessary to test LED lighting. This article will introduce large and thorlabs integrating sphere and the newport integrating sphere system as an efficient and accurate method for testing LED lighting.

LISUN LPCE-2 Integrating Sphere Spectroradiometer LED Testing System is for single LEDs and LED lighting products light measurement. LED’s quality should be tested by checking its photometric, colorimetric and electrical parameters. According to CIE 177, CIE84,  CIE-13.3, IES LM-79-19, Optical-Engineering-49-3-033602, COMMISSION DELEGATED REGULATION (EU) 2019/2015, IESNA LM-63-2, IES-LM-80 and ANSI-C78.377, it recommends to using an array spectroradiometer with an integrating sphere to test SSL products. The LPCE-2 system is applied with LMS-9000C High Precision CCD Spectroradiometer or LMS-9500C Scientific Grade CCD Spectroradiometer, and a-molding integrating sphere with holder base. This sphere is more round and the test result is more accruate than the traditional integrating sphere.

High Precision Spectroradiometer Integrating Sphere System LPCE-2(LMS-9000)

1. Thorlabs Integrating Sphere
A thorlabs integrating sphere is a device used to test large-sized lighting fixtures. Its structure consists of a large spherical reflector and a holder. The interior of the integrating sphere should be coated with a high reflectivity material to ensure the accuracy of the test. During the test, the LED lighting fixture is installed on the integrating sphere holder, and the light emitted by the fixture is irradiated into the sphere. The reflective material inside the sphere uniformly reflects the light in all directions of the sphere. Then, instruments such as a spectrometer or photometer are used to measure the luminance inside the sphere. By analyzing the measurement data, performance indicators such as brightness, intensity, and color temperature of the LED lighting fixture can be obtained.

The advantages of a thorlabs integrating sphere  are its suitability for testing high-power and large-sized lighting fixtures, as well as high testing accuracy and reliability.However, its disadvantages are high cost and inconvenient use. In addition, due to the loss of reflective material, there may be some measurement errors in the results of large integrating spheres.

2. Newport Integrating Sphere
A newport integrating sphere is a device used to test small-sized lighting fixtures. Its structure is similar to that of a large integrating sphere, but it is smaller in size and more portable. Small integrating spheres can be used to test small-sized LED lighting fixtures, such as LED bulbs and LED spotlights. The testing principle is the same as that of a large integrating sphere, where the lighting fixture is installed on the integrating sphere holder, and the light emitted by the fixture is irradiated into the sphere. The reflective material inside the sphere uniformly reflects the light in all directions of the sphere. Then, instruments such as a spectrometer or photometer are used to measure the luminance inside the sphere, thereby obtaining performance indicators of the LED lighting fixture.

The advantages of a newport integrating sphere are low cost, easy portability, and ease of use. Due to its smaller size, it can be used to test lighting fixtures that are difficult to test with a large integrating sphere. However, the testing accuracy of a small integrating sphere may not be as high as that of a largeintegrating sphere, and it is more sensitive to the size and position of the lighting fixture.

3. Integrating sphere testing system
An integrating sphere testing system is a testing system that integrates large or newport integrating sphere with other testing equipment. This system automates the testing and data analysis of LED lighting fixtures through control and monitoring of the testing process.

The main components of an integrating sphere testing system include an integrating sphere, light source, spectrometer, photometer, controller, and data processing software. The light source is responsible for providing light, the spectrometer and photometer are used to measure luminance and spectral distribution, the controller controls the testing process, and the data processing software analyzes and processes the measurement data.

When using an integrating sphere testing system to test LED lighting fixtures, the lighting fixture is first installed on the integrating sphere holder, and the controller controls the brightness and color temperature of the light source. The system then directs the emitted light into the integrating sphere, where the reflective material inside the sphere uniformly reflects the light in all directions. The spectrometer and photometer measure the luminance and spectral distribution inside the sphere, and the controller transfers the measurement data to the data processing software for analysis and processing. Finally, based on the analysis results, various performance indicators ofthe LED lighting fixture can be obtained.

The advantages of an integrating sphere testing system are the integration of multiple testing equipment, ease of operation, and high degree of automation. It can improve the accuracy and repeatability of testing, and is suitable for various sizes and types of LED lighting fixtures. However, due to the complexity and high cost of the system, it may face some challenges in practical applications.

By using an integrating sphere testing system, the photometric performance of LED lighting fixtures can be quantitatively evaluated, helping consumers choose lighting fixtures that meet their needs. Here are some testing steps and considerations:
1. Preheating: Before starting the test, the LED lighting fixture should be preheated for a period of time, usually 15-30 minutes. This ensures that the fixture is tested in a stable working state.
2. Set testing parameters: Set the parameters of the testing system according to the requirements, such as the unit of measured luminous flux, the angle of intensity measurement, and the position of illuminance measurement.
3. Placement of the fixture: Place the LED lighting fixture to be tested in the center of the integrating sphere, ensuring that it emits light evenly inside the sphere.
4. Perform measurement: Start the testing system and allow the detectorto measure the light emitted by the fixture. Depending on the requirements, multiple measurements can be taken at different directions and positions to obtain more accurate data.
5. Data analysis: The collected data can be analyzed and processed using software. Light intensity distribution plots, illuminance distribution plots, etc. can be generated to help compare the performance differences between different LED lighting fixtures.

When using an integrating sphere testing system, the following considerations should be noted:
1. Environmental control: To ensure the accuracy of the test results, testing should be conducted in stable environmental conditions, including temperature, humidity, and control of background light.
2. Calibration: Regularly calibrate the testing system to ensure its accuracy. Calibration should be done according to the manufacturer’s recommendations, and each calibration date and result should be recorded.
3. Selecting the appropriate testing system: Different LED lighting fixtures may require different types and specifications of integrating sphere testing systems. Select a system that is suitable for the desired test to ensure accurate test results.

Testing LED lighting fixtures is crucial to ensuring their quality and performance. Large and small integrating spheres, as well as integrating sphere testing systems, provide an efficient and accurate testing method. Large integrating spheres are suitable for testing high-power and large-sized fixtures, with high testing accuracy and reliability buthigher cost. Small integrating spheres are suitable for testing small-sized fixtures, with lower cost and portability, but potentially lower testing accuracy. Integrating sphere testing systems integrate multiple testing equipment, are easy to operate with a high degree of automation, and can improve testing accuracy and repeatability, but are also higher in cost. By selecting the appropriate testing method based on specific needs, the quality and performance of LED lighting fixtures can be effectively ensured.

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.

Please feel free to contact us if you need any support.
Tech Dep: Service@Lisungroup.com, Cell/WhatsApp:+8615317907381
Sales Dep: Sales@Lisungroup.com, Cell/WhatsApp:+8618117273997