Photographing optical lens assembly, imaging apparatus and electronic device

Patent metadata

Field	Value
Publication number	US-12061378-B2
Application number	US-202017088995-A
Country	US
Kind code	B2
Filing date	Nov 4, 2020
Priority date	Jun 20, 2020
Publication date	Aug 13, 2024
Grant date	Aug 13, 2024

Abstract

An imaging apparatus includes a photographing optical lens assembly and an image sensor. The photographing optical lens assembly includes a plurality of lens elements. The plurality of lens elements includes, in order from an object side to an image side, a first lens element, a second lens element and a last lens element. Each of the lens elements has an object-side surface facing the object side and an image-side surface facing the image side. At least one of the lens elements is plastic and at least one of the lens elements has at least one inflection point. There is at least one variable axial distance between adjacent lens elements thereof.

First claim

What is claimed is:

1. An imaging apparatus, comprising a photographing optical lens assembly and an image sensor;
the photographing optical lens assembly comprising a plurality of lens elements which is at least eight and at most ten lens elements, the plurality of lens elements comprising, in order from an object side to an image side, a first lens element, a second lens element and a last lens element; each of the plurality of lens elements having an object-side surface facing the object side and an image-side surface facing the image side, and the image sensor being disposed on the image side of the last lens element;
wherein the object-side surface of a seventh lens element is convex in a paraxial region thereof, at least one of the lens elements is plastic, and at least one of the lens elements comprises at least one inflection point; there is at least one variable axial distance between two adjacent lens elements thereof;
wherein a minimum among Abbe numbers of the lens elements of the photographing optical lens assembly is Vdmin; the photographing optical lens assembly comprises an object distance between an imaged object and the object-side surface of the first lens element; when the object distance is infinite, an axial distance between the object-side surface of the first lens element and the image sensor is TLinf, a focal length of the photographing optical lens assembly is finf, and an any one of the at least one variable axial distance is ATinf; when the object distance is 500 mm, the any one of the at least one variable axial distance is ATmacro, and the axial distance between the object-side surface of the first lens element and the image sensor is TLmacro, an axial distance between the first lens element and the second lens element is smaller than an axial distance between the seventh lens element and an eighth lens element; and the following conditions are satisfied:
0.60 <TL inf/ f inf<2.50;
10.0 <Vd min<28.0; and
0.05<|( AT inf− AT macro)/( TL inf− TL macro)|<0.80.

2. The imaging apparatus of claim 1 , wherein the first lens element has positive refractive power, the second lens element has negative refractive power, a maximum among refractive indexes of the lens elements of the photographing optical lens assembly is Nmax, and the following condition is satisfied:
1.665 <N max<1.780.

3. The imaging apparatus of claim 1 , wherein when the object distance is infinite, the focal length of the photographing optical lens assembly is finf, and an entrance pupil diameter of the photographing optical lens assembly is EPDinf, and the following condition is satisfied:
1.20 <f inf/ EPD inf<2.0.

4. The imaging apparatus of claim 1 , wherein the minimum among Abbe numbers of the lens elements of the photographing optical lens assembly is Vdmin, and the following condition is satisfied:
12.0 <Vd min<20.0.

5. The imaging apparatus of claim 1 , wherein a minimum among central thicknesses of the lens elements of the photographing optical lens assembly is CTmin; when the object distance is infinite, the any one of the at least one variable axial distance is ATinf; when the object distance is 500 mm, the any one of the at least one variable axial distance is ATmacro, and the following condition is satisfied:
0.01<|( AT inf− AT macro)|/ CT min<0.50.

6. The imaging apparatus of claim 1 , wherein when the object distance is infinite, half of a maximum field of view of the photographing optical lens assembly is HFOVinf; when the object distance is 500 mm, half of a maximum field of view of the photographing optical lens assembly is HFOVmacro, and the following conditions are satisfied:
35.0 degrees<HFOVinf<65.0 degrees; and
35.0 degrees<HFOVmacro<65.0 degrees.

7. The imaging apparatus of claim 1 , wherein the photographing optical lens assembly comprises an aperture stop; when the object distance is infinite, an axial distance between the aperture stop and the image sensor is SLinf, the axial distance between the object-side surface of the first lens element and the image sensor is TLinf, and the following condition is satisfied:
0.70 <SL inf/ TL inf<1.0.

8. The imaging apparatus of claim 1 , wherein a sum of central thicknesses of the lens elements is ΣCT, a maximal image height of the photographing optical lens assembly is ImgH; when the object distance is infinite, the axial distance between the object-side surface of the first lens element and the image sensor is TLinf, and the following conditions are satisfied:
0.48 <ΣCT/TL inf<0.80; and
5.20 mm<ImgH<10.0 mm.

9. The imaging apparatus of claim 1 , wherein a maximal image height of the photographing optical lens assembly is ImgH; when the object distance is infinite, the axial distance between the object-side surface of the first lens element and the image sensor is TLinf, and the following condition is satisfied:
1.0 <TL inf/ImgH<1.80.

10. The imaging apparatus of claim 1 , wherein a maximal image height of the photographing optical lens assembly is ImgH; when the object distance is infinite, the any one of the at least one variable axial distance is ATinf, an axial distance between the image-side surface of the last lens element and the image sensor is BLinf, the focal length of the photographing optical lens assembly is finf; when the object distance is 500 mm, the any one of the at least one variable axial distance is ATmacro, the axial distance between the image-side surface of the last lens element and the image sensor is BLmacro, and the following conditions are satisfied:
0.07<|( AT inf− AT macro)/( BL inf− BL macro)|<0.90; and

0.72<ImgH/ f inf<1.80.

11. The imaging apparatus of claim 1 , wherein the last lens element has negative refractive power; a maximal image height of the photographing optical lens assembly is ImgH; when the object distance is infinite, an axial distance between the image-side surface of the last lens element and the image sensor is BLinf, and the following condition is satisfied:
3.70<ImgH/ BL inf<10.0.

12. The imaging apparatus of claim 1 , wherein the imaging apparatus comprises a first driving device and a second driving device; the image-side surface of the last lens element is concave in a paraxial region thereof and comprises a convex critical point in an off-axial region thereof.

13. The imaging apparatus of claim 12 , wherein a central region of an image is corrected when at least one of the plurality of lens elements is moved by the first driving device, and a peripheral region of the image is corrected when at least one of the plurality of lens elements is moved by the second driving device.

14. The imaging apparatus of claim 12 , wherein at least one of the first driving device and the second driving device comprises shape memory alloys or piezoelectric materials.

15. The imaging apparatus of claim 12 , wherein when the first driving device is actuated, an axial distance between any two lens elements of the photographing optical lens assembly remains the same; the image sensor comprises at least 50 million pixels.

16. The imaging apparatus of claim 12 , wherein the at least one variable axial distance changes between the two adjacent lens elements when the second driving device moves one of the two adjacent lens elements; when the object distance is infinite, the any one of the at least one variable axial distance is ATinf; when the object distance is 500 mm, the any one of the at least one variable axial distance is ATmacro; and the following condition is satisfied:
0.07 mm<|( AT inf− AT macro)|*10<1.0 mm.

17. The imaging

Assignees

• Largan Precision Co Ltd

Inventors

• Tseng Yu-Tai
• Huang Hsin-Hsuan

Classifications

• H04N23/55

  Optical parts specially adapted for electronic image sensors; Mounting thereof · CPC title

• G02B7/10

  by relative axial movement of several lenses, e.g. of varifocal objective lens · CPC title

• G02B7/09

  adapted for automatic focusing or varying magnification · CPC title

• G02B3/04

  with continuous faces that are rotationally symmetrical but deviate from a true sphere {, e.g. so called "aspheric" lenses} · CPC title

• G02B27/0012

  Optical design, e.g. procedures, algorithms, optimisation routines · CPC title