Optical system and image pickup apparatus having the same

Pending Publication Date: 2021-12-23
CANON KK
View PDF0 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0004]The present invention provides an optical system that is easy to manufacture and has h

Problems solved by technology

In order to process germanium or silicon into an aspherical shape

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Optical system and image pickup apparatus having the same
  • Optical system and image pickup apparatus having the same
  • Optical system and image pickup apparatus having the same

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0035]FIG. 1 is a sectional view of an optical system 100 according to this example. The optical system 100 is an infrared optical system having a focal length of 18 mm and an F-number of 0.8. The infrared optical system, as used herein, is an optical system that images an object with light having a wavelength of 8 μm or longer. The optical system 100 includes, in order from the object side to the image side, a first lens L11 having a positive refractive power and made of a silicon material, a thin aspherical plate (optical element) P11 made of a silicon material and having an aspherical portion with a thickness that gradually increases from the center to the periphery (or with a thickness that monotonously increases from the on-axis to the outermost off-axis in the section including the optical axis), a diaphragm (aperture stop) S1, a second lens L12 having a positive refractive power and made of a silicon material, a third lens L13 having a positive refractive power and made of a ...

example 2

[0057]FIG. 3 is a sectional view of an optical system 200 according to this example. The optical system 200 is an infrared optical system having a focal length of 14 mm and an F-number of 0.8. The optical system 200 includes, in order from the object side to the image side, a first lens L21 having a positive refractive power and made of a silicon material, a thin aspherical plate P21 made of a silicon material and having an aspherical portion with a thickness that gradually increases from the center to the periphery, a thin aspherical plate P22 made of a silicon material and having an aspherical portion with a thickness that gradually decreases from the center to the periphery, a diaphragm S2, a second lens L22 having a positive refractive power and made of a silicon material, a thin lens L23 having a positive refractive power and made of a silicon material, and a thin aspherical plate P23 made of a silicon material and having an aspherical portion with a thickness that gradually in...

example 3

[0060]FIG. 5 is a sectional view of an optical system 300 according to this example. The optical system 300 is an infrared optical system having a focal length of 50 mm and an F-number of 0.8. The optical system 300 includes, in order from the object side to the image side, a first lens L31 made of a silicon material and having a positive refractive power, a thin aspherical plate P31 made of a silicon material and having an aspherical portion with a thickness that gradually increases from the center to the periphery, a diaphragm S3, a second lens L32 having a positive refractive power and made of a silicon material, and a thin aspherical plate P32 made of a silicon material and having an aspherical portion with a thickness that gradually increases from the center to the periphery. Therefore, it can be manufactured by easy processing such as a bending process used to manufacture the Schmidt correction plate. The thin aspherical plates P31 and P32 are assumed to have a very thin thick...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

An optical system images an object with light with a wavelength of 8 μm or higher, and includes a diaphragm and an optical element having an aspherical surface and disposed at a position different from that of the diaphragm. In a section including an optical axis, a thickness of an optical element monotonously increases from an on-axis to an outermost off-axis or the optical element is the thinnest at a position other than an on-axis and an outermost off-axis. A predetermined condition is satisfied.

Description

BACKGROUND OF THE INVENTIONField of the Invention[0001]The present invention relates to an optical system compatible with infrared light, for example, one suitable for an image pickup apparatus such as a surveillance camera and an in-vehicle camera.Description of the Related Art[0002]There is known an optical system (“infrared optical system”) compatible with light in an infrared range (infrared light, infrared ray) (with a wavelength of about 8 μm to 14 μm). Applying the infrared optical system to the image pickup apparatus can visualize thermal information such as a temperature distribution of an object, which is unavailable in the visible wavelength range (with a wavelength of about 0.4 μm to 0.7 μm). Materials (“infrared materials”) that transmit light in the infrared range used for the infrared optical systems include, for example, germanium (Ge), gallium arsenide (GAAS), chalcogenide, zinc selenide (ZnSe), zinc sulfide (ZnS), silicon (Si) and resin (high density polyethylene, ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G02B9/12G02B5/00G02B9/06
CPCG02B9/12H04N5/33G02B9/06G02B5/005G02B13/14
Inventor DOUJOU, NAOTO
Owner CANON KK
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products