Taking lens system
AssigneeKonica Minolta Opto, Inc.
InventorMasashi Isono
Life of this patent
Estimating the term…
Abstract
A three-lens-element taking lens system for forming an image on a solid-state image sensor has, from the object side, a first lens element having a positive optical power, an aperture stop, a second lens element having a positive optical power, and a third lens element having a negative optical power and having a concave surface pointing to the image side. Of the first and second lens elements, one is a glass lens element and the other is a plastic lens element. The third lens element is a plastic lens element.
Claims23
A three-lens-element taking lens system for forming an image on a solid-state image sensor, comprising, from an object side, a first lens element having a positive optical power, an aperture stop, a second lens element having a positive optical power, and a third lens element having a negative optical power and having a concave surface pointing to an image side,
- wherein, of the first and second lens elements, one is a glass lens element and the other is a plastic lens element,
- wherein the third lens element is a plastic lens element, and
- wherein the following condition is fulfilled:
- 0.3<f/fG<2.6
- where f represents a focal length of the taking lens system as a whole;
- and
- fG represents a focal length of the glass lens element having a positive optical power.
A three-lens-element taking lens system for forming an image on a solid-state image sensor, comprising, from an object side, a first lens element having a positive optical power, an aperture stop, a second lens element having a positive optical power, and a third lens element having a negative optical power and having a concave surface pointing to an image side,
- wherein, of the first and second lens elements, one is a glass lens element and the other is a plastic lens element,
- wherein the third lens element is a plastic lens element, and
- wherein the following condition is fulfilled:
- 0.05<TG/fG<1.35
- where TG represents an axial thickness of the glass lens element having a positive optical power;
- and
- fG represents a focal length of the glass lens element having a positive optical power.
A three-lens-element taking lens system for forming an image on a solid-state image sensor, comprising, from an object side, a first lens element having a positive optical power, an aperture stop, a second lens element having a positive optical power, and a third lens element having a negative optical power and having a concave surface pointing to an image side,
- wherein, of the first and second lens elements, one is a glass lens element and the other is a plastic lens element,
- wherein the third lens element is a plastic lens element, and
- wherein the following condition is fulfilled:
- |f3|/fP<2.6
- where f3 represents a focal length of the third lens element;
- and
- fP represents a focal length of the plastic lens element having a positive optical power.
A three-lens-element taking lens system for forming an image on a solid-state image sensor, comprising, from an object side, a first lens element having a positive optical power, an aperture stop, a second lens element having a positive optical power, and a third lens element having a negative optical power and having a concave surface pointing to an image side,
- wherein, of the first and second lens elements, one is a glass lens element and the other is a plastic lens element,
- wherein the third lens element is a plastic lens element, and
- wherein the following condition is fulfilled:
- 0.05<T3/f<0.5
- where T3 represents an axial thickness of the third lens element;
- and
- f represents a focal length of the taking lens system as a whole.
A three-lens-element taking lens system for forming an image on a solid-state image sensor, comprising, from an object side, a first lens element having a positive optical power, an aperture stop, a second lens element having a positive optical power, and a third lens element having a negative optical power and having a concave surface pointing to an image side,
- wherein, of the first and second lens elements, one is a glass lens element and the other is a plastic lens element,
- wherein the third lens element is a plastic lens element, and
- wherein the following condition is fulfilled:
- VG>58
- where VG represents an Abbe number of the glass lens element having a positive optical power.
A three-lens-element taking lens system for forming an image on a solid-state image sensor, comprising, from an object side, a first lens element having a positive optical power, an aperture stop, a second lens element having a positive optical power, and a third lens element having a negative optical power,
- wherein, of the first and second lens elements, one is a glass meniscus lens element and the other is a plastic meniscus lens element, and
- wherein the third lens element is a plastic meniscus lens element having a concave surface pointing to an image side or a plastic biconcave lens element.
Dependencies are inferred from the claim text.