Table 1.

The correlation between distance and light intensity with different light source.

Light source (Passed through color filter)		Standard white light (400–700 nm)		Red light (640–700 nm)		Blue light (425–490 nm)		Green light (500–560 nm)		Yellow light (570–620 nm)		Magenta light (400–500 nm and 660–700 nm)
Position No.	Distancea	Light intensityb	PPFDc	Light intensityb	PPFD	Light intensityb	PPFD	Light intensityb	PPFD	Light intensityb	PPFD	Light intensityb	PPFD
1	12.0	11898	113.9	3592	35.5	6468	67	6702	67	7785	76.9	7298	74.3
2	16.0	7195	72.4	2349	18.6	4060	41	4262	42	5048	50.7	4754	47.8
3	20.0	4987	51.5	1650	16.3	2868	29	3035	30	3531	35.3	3409	33.5
4	24.0	3755	38.6	1222	12.1	2144	26	2272	24	2625	26.5	2581	25.4
5	26.0	3246	33.8	1075	10.7	1888	19	1982	20	2318	23.1	2263	22.3
6	28.0	2932	30.6	969	9.6	1673	17	1747	18	2076	20.6	2043	20.5
7	30.0	2366	24.5	779	7.8	1349	15	1371	14	1657	16.7	1654	16.1
8	38.0	1875	20.1	638	6.3	1120	11	1153	12	1354	13.6	1361	13.3
9	42.0	1523	16.8	537	5.3	923	9.5	927	10	1138	11.3	1129	11.2
10	Dark	ND	ND	ND	ND	ND	ND	ND	ND	ND	ND	ND	ND

^aDistance is defined the straight distance from the light source by cm.

^bLight intensity is defined as the lumen flux in unit area (lux = lm/m²/s)

^cPPFD is defined as the photosynthetic photon flux in unit area (μmole/m²/s), in which wavelength of light range from 400 to 700 nm.

ND: not-determined.