| 摘要 |
PROBLEM TO BE SOLVED: To provide a lens glass material for an on-vehicle camera, which is excellent in resistance to acid rain or to a chemical, which is scarcely scratched because of having sufficient hardness, which has little characteristic deterioration caused by ultraviolet rays, which has a high refractive index, and which is suitable for constituting an imaging lens mounted on the on-vehicle camera which will be exposed to a severe environment; and to provide a lens for the on-vehicle camera using such a lens glass material for the on-vehicle camera.SOLUTION: A lens glass material for an on-vehicle camera satisfies one of following conditions, namely: having the first class result in a measurement of resistance to acids by a powder method specified in Japanese Optical Glass Industrial Standards; having the sixth or higher class result in a measurement of Knoop hardness by a measurement method specified in the standard; resulting in 2% or less in a measurement of solarization by a measurement method specified in the standard; and resulting in 100×10°Cor less in a measurement of coefficient of average linear expansion coefficient by a measurement method specified in the standard. |
