Endoscope objective lens

摘要

Manufacturing errors are suppressed, a variable magnification function is provided, and good observation with aberrations appropriately corrected is performed. Provided is an endoscope objective lens including, in order from an object side, a positive first lens group, a negative second lens group, and a positive third lens group, in which the first lens group has a meniscus lens; and a normal observation state (wide angle end) and a magnifying observation state (telephoto end) can be switched between by moving the second lens group on the optical axis, and the following conditions are satisfied;
−9where fM represents the focal distance of the meniscus lens, fW represents the entire focal distance for the normal observation, and f2 represents the focal distance of the second lens group.

主权项

1. An endoscope objective lens comprising, in order from an object side, a positive first lens group, a negative second lens group, and a positive third lens group,
wherein the first lens group has only one meniscus lens; and a normal observation state (wide angle end) and a magnifying observation state (telephoto end) can be switched between by moving the second lens group on an optical axis, and the following conditions are satisfied;
−9