Page 72 - JCBP-3-4

Journal of Clinical and
Basic Psychosomatics Intervention through natural/digital art

A C

B

Figure 2. Examples of pixel light-emitting diodes (LEDs) on the trees and ground. (A) Three trees illuminated with champagne-gold LEDs as the main
focal points. (B) Full-color pixel LEDs arranged on the ground to represent ripples. (C) The backwoods reflecting the light from a full-color-controlled
LED floodlight.

A B Table 1. Color index data for champagne-gold light-emitting
diodes measured using the spectrometer

Item Color index Measured value
1 Color temperature 2306 K
2 Color rendering index 53.0
3 Illuminance @ 1 m 79.10 lux (lm/m )
2
C D 4 Centre wavelength (λp) 592 nm (Figure 3C)
5.1 CIE 1976 color space (u’) 0.2818 (Figure 3D)
5.2 CIE 1976 color space (v’) 0.5466 (Figure 3D)
Abbreviation: CIE: Commission Internationale de l’Éclairage.

The color rendering index (CRI) (Table 1, Item #2) is
defined by the “Commission Internationale de l’Éclairage”
Figure 3. Color light characteristics of champagne gold light-emitting (CIE) and refers to a comparison of the light quality of
diodes (LEDs). (A) Schematic diagram of optical property measurement natural light sources and artificial light sources. CRI is
for string LEDs. (B) Photographic example of champagne gold measured on a scale from 0 to 100, with values closer to
LEDs. (C) Light source spectrum of the LED used. (D) “Commission 100 indicating light that more closely resembles natural
Internationale de l’Éclairage” 1976 color space.
sunlight. The sample in this study showed an average CRI
The optical characteristics of the LED string lighting value.
fixtures were preliminarily obtained through spectral Basic light characteristic indices, including illuminance
measurement data, which are summarized in Figure 3A, (Table 1, Item #3) and the maximum peak center value of
14
B, and Table 1. the light wavelength (Table 1, Item #4 and Figure 3C), were
measured.
The color temperature (Table 1, Item #1) is a scale
used to express the color of light emitted by a source in The CIE 1976 color space is one of the uniform color
quantitative terms. The unit of measurement is Kelvin spaces defined by the CIE in 1976, designed to achieve
(K), which corresponds to the unit of thermodynamic uniformity in formula differences. It was based on the
temperature. For general lighting, the color temperature earlier CIE 1931 XYZ color space and aimed to improve
of incandescent light is around 3,000 K, natural white usability. This color space is widely used in LED light
around 4,000 K, daylight white around 5,000 K, and sources for lighting as well as in displays and other
daylight around 6,500 K (all central values). The applications.
sample in this study had a significantly warm color In Figure 3D, the x-axis (u’) represents the transition
temperature at 2,306 K, corresponding to a champagne from green to red (Table 1, Item #5.1), while the y-axis (v’)
gold hue. (Table 1, Item #5.2) represents the transition from blue to

Volume 3 Issue 4 (2025) 66 doi: 10.36922/jcbp.5740