TrueDaylight for Color Grading of Gemstones
The TrueDaylight is a new type
of daylight simulator. The TrueDaylight consists of a halogen lamp and a series of filters
(two or more filters are arranged one after another) to simulate the northern window
daylight for color grading of gemstones as well as for colorimetric purposes. The
metamerism index of the new daylight simulator is MIvis B or better in the visible range,
and the spectral power distribution matches that of the CIE standard daylight D65 very
well. Figure 1 shows the spectral power distribution of the new filtered halogen daylight
simulator.
Figure 1. The spectral power distribution of
the TrueDaylight simulator.
We provide two types of the TrueDaylight D65
daylight simulator: 1. Task light, and 2. Project light. The task light is used on desk or
clipped on shelf, and the project light is for lighting in a color grading room. Figure 2
shows the two types of TrueDaylight D65 daylight simulators.
Figure 2. Two types of the TrueDaylight. A.
task light, and B. project light.
The TrueDaylight D65 daylight simulator
meets all ASTM, ISO, CIE standards for the D65 daylight simulator, and it is the only
commercial available daylight simulator that meets the requirement of metamerism index B
or better in the visible range for color grading and color matching in the world.
Specifications:
Color
Temperature (Tc): 6500
+/-300 K
Metamerism Index in the Visible Wavelength Range (MIv): B or Better
Color Rendering Index (CRI):
> 95
Illumination Level: 540 - 2150 lx
Beam Angle: 12, 24 and 36 degrees
Average Life: 4000 hours
Note:
The quality of daylight simulators shall be assessed by the metamerism index. Color
Rendering Index is not recommended for assessing the quality of daylight simulators by
ASTM, CIE and ISO.
Flash TrueDaylight
Flash TrueDaylight is for estimating gem color under daylight. It emits high quality
daylight spectrum. It is potable and easy to use. It provide daylight anytime at anywhere!
Liu Research Laboratories, LLC
