An integrating sphere (also known as an Ulbricht sphere) is an optical component consisting of a hollow spherical cavity with its interior covered with a diffuse white reflective coating. It is equipped with a small hole for entrance and exit ports. It is also known as ‘’a sphere with a light source’’. Its relevant property is a uniform scattering or diffusing effect.
An integrating sphere can be the perfect tool for many reflectance applications. It provides a larger collection area than a reflection probe. It is an excellent tool for maintaining a fixed measurement geometry between the sample and illumination source. It features an internal light source which delivers diffuse illumination to the sphere.
You can also use an external light source through a fiber attached through the S port to illuminate at 8 degrees. You can collect either through the eight degrees s port or through the r port. R stands for ‘’reference,’’ and this port can also couple an optical fiber to a second channel in the spectrometer. This channel can then be used to monitor the stability of the internal light source.
To set up, simply attach a fiber from your spectrometer to the integrating sphere through the sample port labelled. This is known as your collection fiber. If using an internal light source, plugin the integrating sphere and switch it on.
If you are using an external light source, attach the input fiber from your light source through the s port instead. Collect through the r port. The IFP ref is fitted with a glass trap for trapping the specular reflection. When opened, it creates a gap in the sphere’s surface positioned at 8 degrees. The same angle as the s port means that all the specular reflection from your sample is lost. You will measure only diffused reflection. It fills in the gap when closed, and specular reflection is retained and included in your measurement.
Ensure the gloss trap is kept in the same position for reference and sample measurements. Whichever light source you are using, make sure you give it time to warm up. Make sure that the light source is producing a stable output. Use a reference standard with properties as close to your sample surface as possible such as the Stan SSH for high reflectivity specular reflectance. Use STAN SSL for low reflectivity specular reflectance or the ws1 for diffuse reflectance.
When taking the dark measurement, it is very important that you take the dark with the light source. So, your dark measurement takes into account your whole optical system. The objective is to measure with zero per cent reflection through the reflectance port with the light source on. Either place a dark tile with very low reflectance over the port or face the sphere’s reflectance port into a dark box or dark room with no external light. It is very important to improve the accuracy of your measurement.
An integrating sphere is a spherical shell whose inner surface is given a suitable coating such that the coating provides a highly diffuse surface. It has a very high reflectivity of more than 95%; such coatings are possible, for example, using barrier sulphate magnesium oxide and so on. LISUN also offers some patented surfaces which give you essentially a very highly diffuse reflecting surface.
A straight line shows a beam of light. Of course, this is the incident light that may be monochromatic and not necessary. That means it is coming from a monochromatic source, or it is from a polychromatic source which has been monochromatic using a monochromatic matter. So, as it comes and falls on the spherical surface, it is reflected in all the directions, as indicated by the arrow.
Because of the high reflectivity of the surface, most of the light will be reflected, and if you follow, what happens to the one which is reflected in the particular direction. You will notice it again falling on another part of the sphere, reflected in all the directions. One of them is coming here again and getting reflected at this point. It essentially falls on the reflecting sample after several reflections.
Hence, the light which is incident through this port or this hole is falling on a small area of the sphere at this particular location. It gets reflected in all directions, and the light received by the reflecting sample comes from all directions. The light of radiation undergoes a larger number of reflections, and it is integrated over all the directions reaching this surface.
So, in the end, what we have is illumination on the sample, which is diffused and coming from the entire hemisphere. That is why the surface is exposed or illuminated by radiation coming on along all the hemispherical directions of the hemisphere.
LPCE-2 (LMS-9000) Integrating Sphere Spectroradiometer LED Testing System is manufactured by LISUN for single LEDs and LED lighting products light measurement. LED’s quality is tested by checking its photometric, colorimetric and electrical parameters.
It recommends using an array spectroradiometer equipped with an integrating sphere for testing the SSL products. The LPCE-2 system is applied with LMS-9000C High Precision CCD Spectroradiometer or LMS-9500C Scientific Grade CCD Spectroradiometer.
This integrating sphere is manufactured by LISUN and is available for sale. You can explore its further details by visiting the official website.
An integrating sphere collects the electromagnetic radiation from a completely external source to the optical device. It collects these radiations, usually for flux measurement or optical attenuation. The radiation is introduced into an integrating sphere, striking the reflective walls. In addition, it undergoes multiple diffuse reflections.
Yes, there are multiple versions available of integrating spheres on the official website of LISUN. You can explore the details of every product by visiting the official website.
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.LPEC-2(LMS-9000)