Tel:+86 769-22667715
RayClouds Photoelectric Technology Co.,Ltd.
RayClouds Photoelectric Technology Co.,Ltd.

Important Evaluation Parameters of Indoor Lighting

The evaluation of interior lighting not only includes basic photochromic electrical parameters like luminous flux, color temperature, color rendering index, service life, nominal voltage and other strict referential standards, but also some vital evaluation parameters, such as luminance, glare level and luminance limit curve. Following are crucial ones among those parameters.

Luminance refers to the physical quantity of a luminous body's (refractive body's) surface luminous intensity. The human eye observes the light source from one direction, and the ratio of the light intensity in this direction to the area of the light source "seen" by the human eye is defined as the unit luminous intensity of the projected area. The unit of luminance is Candela/m2 (cd/m2), and the luminance intensity can be tested with a spectroradiometer. 

The luminous quality is related to the luminous limit of the light. If the luminous intensity is too high in the field of view, it can produce uncomfortable glare, and even disabling glare. Serious glare directly affects labor productivity and even induces eye disease.

Glare: if there is object of high luminous intensity, sharp luminous contrast or extreme contrast in time or space in field of view, it can cause discomfort to our visual sense or lower visual performance, or both. Glare is the most important factor that affects quality of lighting. The degree of glare is related with luminous area, lighting surface luminance, background luminance, as well as direction and position of view. In this regard, the design of light should limit the lighting luminance. In normal circumstances, eyes mostly stay horizontally indoors. Thus, lights are prone to be affected by glare between 60°~90°degree. Direct glares are generated between 45°~90°.

According to the different requirements for lighting quality in lighting application, CIE divides the direct glare of indoor common lighting into 5 quality grades from A to E. The luminance limit curve recommended by CIE is the standards and methods to evaluate the direct glare of general indoor luminaires. Controlling direct glare is controlling the intensity of light in this direction. That means  limiting the brightness of the luminaire between 45 <γ< 85 degrees. To evaluate whether the brightness of the light meets the requirements of limiting glare, first is to draw the brightness curve of the light. The curve is then placed in the luminaire brightness limit curve table for comparison to see if the recommended brightness is out of recommended luminous range. However, the lights of the lighting is transmitted in three-dimensional space, in order to formulate a plan easy to practice, we only limit the luminance of typical plane C. If optical axes are symmetric, we can take half-plane of C0 and C90.

If there is need to evaluate photochromic electrical parameters, optical measurement systems provided by RayClouds can meet all testing needs. In addition, RayClouds provides systemic testing solutions for lighting. 

If you are in search of such a supplier, don't hesitate to contact RayClouds.

Related News
  • Some Information about Spectrometer

    Some Information about Spectrometer

    December 11, 2020When we talk about spectroscopy, we generally refer to "atomic emission spectroscopy," where the wavelengths of elements in photoelectric spectroscopy are the atomic and ionic spectra of the...view
  • LED Fast LED Photochromic Tester Function

    LED Fast LED Photochromic Tester Function

    July 11, 2019The LED Photochromic Tester developed and manufactured by our company is mainly used for fast spectrophotometric color separation of high-power LED, and is suitable for on-line sorting of high-power L...view
  • What is Medium Size Optical Measurement System

    What is Medium Size Optical Measurement System

    July 11, 2019Medium size optical measurement system can analyze and measure the reflection and transmission characteristics of material surface in all directions. The measurable parameters include bidirectional tr...view
  • New trend of automotive display panel: 3D glass

    New trend of automotive display panel: 3D glass

    July 11, 2019With the improvement of people's living standards, the demand for family cars increases greatly. Influenced by intelligence and network connection, the functions of on-board entertainment system are b...view
  • Complete Application of Chromatic Aberration Meter

    Complete Application of Chromatic Aberration Meter

    December 11, 2020Colorimeters are used in a wide variety of applications in the printing, painting, plastics, textile, automotive, and food industries.Color deviation has become a problem in the color printing, textil...view
  • Imaging Brightness Period-Wrong Judgement is still Unavoidable

    Imaging Brightness Period-Wrong Judgement is still Unavoidable

    May 15, 2019First, we simplify the problem, holding the view that the imaging luminance meter, lens distortion, spectral matching and correction have reached the level of LMK imaging luminance meter. The display ...view