Abstract: Light source devices for photography using LED elements as a light source known in the prior art provide insufficient quantity of light, and the inability to avoid size increases in order to generate a sufficient quantity of light has been problematic. A photography light source device 1 according to the present invention has a light source comprising a plurality of LED elements 2 generating white light or light of the three primaries and arranged in one or more rows parallel with the direction of the longer side of the photograph, a case 3 having a lens on which linear fresnel cuts 3a have been applied in a linear direction parallel to the arrangement direction is mounted on the LED element 2, and upon lighting of the LED element 2, drive is performed with a current of between 3 and 50 times the magnitude of the rated current thereof and a lighting duration of between 10 and 600 msec.

Abstract: Light source devices for photography using LED elements as a light source known in the prior art provide insufficient quantity of light, and the inability to avoid size increases in order to generate a sufficient quantity of light has been problematic. A photography light source device 1 according to the present invention has a light source comprising a plurality of LED elements 2 generating white light or light of the three primaries and arranged in one or more rows parallel with the direction of the longer side of the photograph, a case 3 having a lens on which linear fresnel cuts 3a have been applied in a linear direction parallel to the arrangement direction is mounted on the LED element 2, and upon lighting of the LED element 2, drive is performed with a current of between 3 and 50 times the magnitude of the rated current thereof and a lighting duration of between 10 and 600 msec.

Abstract: A high pressure electric discharge lamp adapted to utilize dielectric barrier discharges can include an arc tube having a discharge space that contains at least a rare gas and an outer tube airtightly surrounding the arc tube. At least one material selected from Ne, Ar, Kr, Xe, F2, Cl2, Br2, I2 and N2 or a mixture thereof that are apt to produce a dielectric barrier discharge can be filled in the space between the arc tube and the outer tube at pressure preferably between 1.3 and 100 [kPa] and more preferably between 40 and 80 [kPa]. The type and the pressure of the rare gas contained in the space is selected as to make the dielectric barrier discharge starting voltage in the space lower than the discharge starting voltage in the discharge space.

Abstract: A high pressure electric discharge lamp adapted to utilize dielectric barrier discharges can include an arc tube having a discharge space that contains at least a rare gas and an outer tube airtightly surrounding the arc tube. At least one material selected from Ne, Ar, Kr, Xe, F2, Cl2, Br2, I2and N2 or a mixture thereof that are apt to produce a dielectric barrier discharge can be filled in the space between the arc tube and the outer tube at pressure preferably between 1.3 and 100 [kPa] and more preferably between 40 and 80 [kPa]. The type and the pressure of the rare gas contained in the space is selected as to make the dielectric barrier discharge starting voltage in the space lower than the discharge starting voltage in the discharge space.