| 摘要 |
PROBLEM TO BE SOLVED: To provide a trigonal lanthanum fluoride single crystal capable of hardly generating transparency deterioration due to white turbidity when manufactured, the trigonal lanthanum fluoride single crystal being used as an optical component, such as a laser phase plate and an optical window material and used as the laser phase plate.SOLUTION: The lanthanum fluoride single crystal includes an alkaline earth metal, such as barium and strontium added when the lanthanum fluoride single crystal is grown. The lanthanum fluoride single crystal having no white turbidity during growth and 85%/mm or more of the internal transmissivity of a light having a wavelength of 9.3 μm is efficiently obtained and can be used for various applications using an infrared laser, such as a carbonic acid laser.SELECTED DRAWING: Figure 1 |
