Abstract: Fluorescent lamp 100 has a light color with a correlated color temperature higher than 10000 [K] and lower than 17000 [K] and Duv in a range of ?2.5 to 5, comprising arc tube 10 and phosphor layer 20 which includes at least: a red emitting rare-earth phosphor with a main emission peak (11) in 605-625 [nm]; a green emitting rare-earth phosphor with a main emission peak (12) in 540-550 [nm]; and a blue emitting rare-earth phosphor with a main emission peak (13) in 440-460 [nm], an action function efficiency of melatonin suppression for per unit luminous flux is higher than 1.0, and a general color rendering index Ra is 80 or higher. With the stated structure, the fluorescent lamp 100 suppresses melatonin secretion thereby achieving effects of adjusting biological rhythms and promoting wakefulness of living bodies, and also remedies the shortcomings in color rendering characteristics of the light source.

Abstract: A fluorescent lamp includes a phosphor layer containing a blue phosphor having an emission peak in the 440 to 470 nm wavelength range, a green phosphor having an emission peak in the 505 to 530 nm wavelength range, a green phosphor having an emission peak in the 540 to 570 nm wavelength range, and a red phosphor having an emission peak in the 600 to 670 nm wavelength range. The ratio I1/I2 of the emission peak energy I1 in the wavelength range of 505 to 530 nm to the emission peak energy I2 in the wavelength range of 540 to 570 nm is not less than 0.06. The color temperature of the lamp is not more than 3700 K.

Abstract: A discharge lamp which radiates visible light having the following lights combined: light having an emission peak in 400 to 490 nm wavelength range in a blue spectral region; light having an emission peak in a 500 to 550 nm wavelength range in a green spectral region; and light having an emission peak in 600 to 670 nm wavelength range in a red spectral region. The color point of the radiated light lies within a region common to the following regions: a region bounded by an ellipse with a color point (u, v)=(0.224, 0.330) as a center thereof, a major axis of 0.056, a minor axis of 0.024, and an angle from the u axis of 20 degrees in the CIE 1960 UCS diagram; a region bounded by an ellipse with a color point (u, v)=(0.224, 0.330) as a center thereof, a major axis of 0.078, a minor axis of 0.014, and an angle from the u axis of 30 degrees in the CIE 1960 UCS diagram; a region bounded by an ellipse with a color point (u, v)=(0.235, 0.335) as a center thereof, a major axis of 0.

Abstract: A phosphor host compound is produced from a host compound material. Then, the host compound and a trivalent europium compound are reacted in a reducing atmosphere to generate a desired divalent europium-activated phosphor. If the divalent europium-activated phosphor is generated in this manner, a chemical reaction between the raw material for the host compound and the trivalent europium compound can be suppressed. Therefore, variations in the luminescent color among different production lots of the phosphor can be suppressed, and a phosphor with high color purity can be provided with high repeatability.

Abstract: A control system for a cable television transmission line which has functions of collecting and controlling data. Information is collected by generating an instruction and transmitting same to a microcomputer by space communication. Furthermore, the operating conditions of a remote cable television line amplifier can be changed by generating an instruction from the microcomputer.