| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical recorder having a condenser lens of material which has an extremely high refractive index, is excellent in transmittance, allows easy production and is extremely excellent in terms of workability. SOLUTION: This optical recorder has an objective lens 4 for converging a laser beam L to be cast to a prescribed beam diameter for the purpose of executing information recording to an optical recording medium D and the condenser lens 5 for further condensing the laser beam L transmitted through the objective lens 4 and casting the optical recording medium D with this beam. The condenser lens 5 consists of a single crystal of any among lithium niobate, lithium tantalate, futile, lead molybdate, tellurium dioxide, strontium titanate and zirconium oxide. |
