Tag Archives: atmosphere

Color Shift

COLOR SHIFT

  • Aging UV exposure may cause plastics to change color
  • Operating conditions and contaminants in the atmosphere may cause color changes

MACADAM ELLIPSE

  • Defines the color point specification of lamps
  • Guidelines for how a person can distinguish between similar colors
  • 2 step ellipse: 2 times the just noticeable difference in color

BINING

  • Measure the output of the LEDs AND sort them into various ranges, or bins, before sale, based on color and flux
  • Size and range of colors of the bins is critical to determine how close a match the LEDs will have to each other and the color variation between units
  • All supplied LEDs must fall within a 2 step macadam ellipse [lm-79 and lm-80 of IESNA]

COLOR RENDERING INDEX

  • Measure of color fidelity
  • Does not account for object color shifts that increase color saturation which can enhance visual preferences, color discrimination ability and visual clarity

COLOR QUALITY SCALE

  • Being developed by the national institute of standards and technology to be considered for the TC 1-69
  • Ability to account for the direction of object color shifts
  • Represents the overall color quality of products for all types of light sources