| 摘要 |
<p>The optical system includes first (positive) and second (negative) lens units arranged in order from an object side to an image side, and an aperture stop disposed further on the image side than the second lens unit. The first lens unit includes at least one first optical element satisfyingφGH>0.0,υdGH<39.5 and ndGH>1.70. The optical system satisfies 0.65<|φ2/φ1|<6.00 and 0.45<|ΣφGH×φ2/φ12|<4.00.φGH represents a refractive power of the first optical element when light-entrance and light-exit surfaces thereof are in contact with air,υdGH and ndGH respectively represent an Abbe number and a refractive index of a material forming the first optical element for a d-line,φ1 andφ2 respectively represent the refractive powers of the first lens unit and the second lens unit, andΣφGH represents a sum total of the refractive powerΣφGH of the at least one first optical element.</p> |
