UPRtek Handheld Spectrometer –Technology and LED Optical Measurement Function FAQ.

Most commonly used measurement parameters and optical principles of the spectrometer are explained as follows in order to improve users application and know-how on international optical metrics. We hope you can find them useful and gain a knowledgeable information by referring to the answers below:

If you encounter any problems which is not listed below, please fill out the form and we will reply as soon as possible. Thank you for your cooperation.

What is CRI (Color Rendering Index)?

What is CRI (Color Rendering Index)? It is a metric used to measure the ability of a light to bring out colors in objects (i.e. Color Rendering). Lights with a high CRI rating can make store products look brilliant and vibrant. Other lights with low CRI ratings will make the same products drab and lifeless.Read More

What is CQS (Color Quality Scale)?

Yet another rendering index is the CQS or Color Quality Scale developed by the NIST (National Institute of Standards and Technology), an agency of the United States Department of Commerce.  CQS is also aimed at remedying the deficiencies of the CRI (Ra) indexing system. Read More

What is IES TM-30-15?

TM-30-15 is a color rendering index system published by IES (Illuminating Engineering Society).  A color rendering index system indicates how well a light, when shining on objects, can reproduce the object’s color accurately (compared to a black body radiator – e.g., the sun).  TM-30-15 is next in a line of predecessor CRI systems (CIE CRI, GAI, CQS), each intended to improve on previous designs.  In this article, we explain TM-30-15, its advantages, and why it’s important. Read More

What is TLA (Temporal Light Artifacts) ?

What is TLA or Temporal Lighting Artifacts?  They are mostly visual abnormalities or anomalies caused by pulsating or flickering lights.  Most times it’s hardly noticeable but it can have annoying side effects and even cause catastrophic events. Read More

What is Flicker Metrics (Percent Flicker, Flicker Index, SVM) ?

This article compares three flicker metrics regarding percent flicker, flicker index and SVM. The comparison includes the definition comes from which organization, the definition of itself, calculation formula and the description of the range. If you want to know more about which products have related measurement functions, please click on the relative products tab. Read More

What is Cosine Correction?

Cosine is a mathematical function used to calculate and specify the characteristics (length & angles) of triangles (Trigonometry). Below right picture is the cosine correction comparison between MK350S Premium and Lambert’s Cosine Law. The ideal value of the red circle was described by Johann Hein¬rich Lambert in 1760 and is called “Lambert’s Cosine Law”. Basically it shows how light intensity changes as the angle of the light changes. MK350S Premium cosine receiver is the blue circle; the optimized cosine and Lambert’s cosine law are almost overlapped. It is more in line with international standards for illuminance measurement – JIS AA and DIN B standards and reduced measurement errors effectively. Read More

What is the recommended measuring distance using UPRtek handheld spectrometer?

It depends on users’application needs. Users can adjust the distance of measuring based on their requirements. For example, when a designer sets up the internal lighting and finds out that the light intensity is insufficient in a specific area, the general practices are to increase the numbers of the lights or adjust the installation of height from above to below to make the best display of the whole area. In the same way, you can fix it reversely when lights emit too much intensities. Therefore, users can quantify the light source, get the illuminance value (Lux) with MK350 series handheld spectrometers as well as adjust the numbers and height of the fixtures based on their needs on the current lighting demands. MK350 handheld spectrometers are the best helper to detect the light quality and intensity changes which improve the lighting visual experiences and meet the requirements of the energy saving needs. Read More


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    United Power Research and Technology

    UPRtek (est. 2010) is a manufacturer of portable, high-precision light measurement instruments; Handheld Spectrometers, PAR meters, Spectroradiometers, Light Calibration Solutions.

    UPRtek HQ, R&D and manufacturing are all based out of Taiwan, with Worldwide representation through our certified Global Resellers.

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