CN211236416U

CN211236416U - Fatigue monitoring lens

Info

Publication number: CN211236416U
Application number: CN201921864527.3U
Authority: CN
Inventors: 冷家开; 黄福建; 陈庆峰; 宋政娟
Original assignee: Shinwa Ind Ltd
Current assignee: Shinwa Ind Ltd
Priority date: 2019-11-01
Filing date: 2019-11-01
Publication date: 2020-08-11
Anticipated expiration: 2029-11-01

Abstract

The utility model discloses a fatigue monitoring lens, including first lens (G1), second lens (G2), third lens (G3), fourth lens (G4) and fifth lens (G5), first lens (G1), second lens (G2), third lens (G3), fourth lens (G4) and fifth lens (G5) set gradually from the object space to the image space; the first lens (G1) is a plano-convex spherical lens, the second lens (G2) is a biconcave spherical lens, the fourth lens (G4) is a biconvex spherical lens, the third lens (G3) and the fifth lens (G5) are both meniscus spherical lenses, the third lens (G3) is convex to the image direction, and the fifth lens (G5) is convex to the object direction. The utility model is used for optical lens of fatigue control.

Description

Fatigue monitoring lens

Technical Field

The utility model relates to an optical lens technical field, concretely relates to tired monitoring camera lens.

Background

With the improvement of the technology and the continuous improvement of the market demand, the technology of the vehicle-mounted active safety equipment is rapidly developed and gradually popularized, fatigue driving is taken as an important part in the active safety field, the active safety equipment is developed towards the miniaturization direction, the requirement is small in size, the resolution is high, and the lens can realize day and night confocal function. However, such special lenses are rarely provided in the current market, and generally have large volume, low resolving power and high cost, so that the installation requirement of such a system on the miniaturization of the volume of the vehicle-mounted active safety equipment is difficult to meet, the resolving power is low, and the application effect is poor; the cost is also high.

SUMMERY OF THE UTILITY MODEL

The utility model provides a technical problem to not enough in the background art, provide a tired monitoring camera lens that can solve.

In order to solve the technical problem, the technical scheme of the utility model is that: a fatigue monitoring lens comprises a first lens, a second lens, a third lens, a fourth lens and a fifth lens, wherein the first lens, the second lens, the third lens, the fourth lens and the fifth lens are arranged in sequence from an object side to an image side; the first lens is a plano-convex spherical lens, the second lens is a biconcave spherical lens, the fourth lens is a biconvex spherical lens, the third lens and the fifth lens are meniscus spherical lenses, the third lens is convex to the image space, and the fifth lens is convex to the object space.

Furthermore, the first lens, the second lens, the third lens, the fourth lens and the fifth lens are all made of transparent glass materials; the materials of the first lens, the third lens, the fourth lens and the fifth lens meet the condition that Nd is larger than or equal to 1.70, the material of the second lens meets the condition that Vd is larger than or equal to 35, wherein Nd is the d-light refractive index of the lens material, and Vd is the d-light Abbe constant of the lens material.

Further, the relationship between the total optical length of the lens and the effective focal length value satisfies that ttl/f is less than or equal to 2, where ttl is the total optical length of the lens, and f is the effective focal length value of the lens.

Further, the relation between the focal length value of the second lens and the effective focal length value of the lens meets | f2/f | ≦ 1 of more than or equal to 0.5, wherein f2 is the focal length value of the second lens, and f is the effective focal length value of the lens.

Further, the relation between the focal length value of the third lens and the effective focal length value of the lens meets the condition that | f3/f | is less than or equal to 1 and less than or equal to 2, wherein f3 is the focal length value of the third lens, and f is the effective focal length value of the lens.

Further, the lens further comprises a diaphragm, and the diaphragm is arranged on the front side of one side, close to the object, of the first lens.

Furthermore, the applicable imaging spectrum wavelength range of the lens is any wavelength between 650nm and 980 nm.

Further, the angular range of the imaging field of view angle of the lens is 40 ° < FOV <80 °, where FOV is field angle.

Further, the aperture value of the lens is F less than or equal to 2.2, wherein F is the aperture value.

The utility model discloses the beneficial effect who realizes mainly has following several: the first lens of the plano-convex spherical structure, the second lens of the biconcave spherical structure, the third lens of the meniscus spherical structure, the fourth lens of the biconvex spherical structure and the fifth lens of the meniscus spherical structure which are arranged in sequence from the object space to the image space are adopted, so that the number of lenses is relatively small, and the spherical lenses are adopted, so that the structure of the lens is simple, the manufacture is easy, the cost of the lens is low, the size of the lens is small, and the requirement of the miniaturization of the volume of the installation equipment can be met; the second lens and the third lens can effectively correct main aberrations such as spherical aberration, field curvature, astigmatism and the like; the fifth lens corrects residual aberration and realizes high-definition resolving power of the lens.

Drawings

Fig. 1 is a schematic structural diagram of a fatigue monitoring lens according to an embodiment of the present invention;

fig. 2 is a MTF graph of a fatigue monitoring lens according to a first embodiment of the present invention;

fig. 3 is a point chart of a fatigue monitoring lens according to a first embodiment of the present invention;

fig. 4 is a field curvature and distortion diagram of a fatigue monitoring lens according to a first embodiment of the present invention;

fig. 5 is a spherical aberration curve diagram of a fatigue monitoring lens according to an embodiment of the present invention.

The drawings are for illustrative purposes only and are not to be construed as limiting the patent; for the purpose of better illustrating the embodiments, certain features of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted; the same or similar reference numerals correspond to the same or similar parts; the terms describing positional relationships in the drawings are for illustrative purposes only and are not to be construed as limiting the patent.

Detailed Description

A fatigue monitoring lens can be used for face recognition and fatigue driving early warning. The optical lens comprises a first lens G1, a second lens G2, a third lens G3, a fourth lens G4 and a fifth lens G5, wherein the first lens G1, the second lens G2, the third lens G3, the fourth lens G4 and the fifth lens G5 are arranged in sequence from an object side to an image side; the first lens G1 is a plano-convex spherical lens, the second lens G2 is a biconcave spherical lens, the third lens G3 and the fifth lens G5 are both meniscus spherical lenses, and the fourth lens G4 is a biconvex spherical lens. In the lens with the structure, the lenses are relatively few, and the spherical lenses are adopted, so that the lens is simple in structure, easy to manufacture, low in cost and small in size, and can meet the requirement of miniaturization of the volume of installation equipment; the second lens G2 and the third lens G3 can effectively correct main aberrations such as spherical aberration, curvature of field and astigmatism; the fifth lens G5 corrects residual aberration, achieving high resolution.

The first lens G1, the second lens G2, the third lens G3, the fourth lens G4 and the fifth lens G5 of the fatigue monitoring lens are all made of transparent glass materials; the materials of the first lens G1, the third lens G3, the fourth lens G4 and the fifth lens G5 meet Nd being more than or equal to 1.70, and the material of the second lens G2 meets Vd being more than or equal to 35; the relation between the optical total length of the lens and the effective focal length value meets the condition that the ttl/f is less than or equal to 2.5; the relation between the focal length value of the second lens G2 and the effective focal length value of the lens is more than or equal to 0.5 and less than or equal to | f2/f and less than or equal to 1, and the relation between the focal length value of the third lens G3 and the effective focal length value of the lens is more than or equal to 1 and less than or equal to | f3/f and less than or equal to 2; the applicable imaging spectrum wavelength range of the lens is any wavelength between 650nm and 980nm, the visible light and infrared light bands are included, and the requirements of face recognition and fatigue driving early warning are met; the angle range of the imaging field angle of the lens is 40 degrees < FOV <80 degrees, and the aperture value of the lens is F less than or equal to 2.2. Therefore, high-definition resolution imaging of the optical lens at the wavelength of 650 nm-980 nm can be further ensured. Wherein Nd is refractive index of d light (central wavelength 589.3 nm) made of lens material, Vd is abbe constant of d light made of lens material, wherein ttl is total optical length of the lens, F2 is focal length of the second lens G2, F3 is focal length of the third lens G3, F is effective focal length of the lens, F is aperture value, and FOV is field angle.

In addition, the optical lens further comprises an optical filter IR and an Image plane Image, wherein the optical filter IR is arranged at the rearmost end position from the object side to the Image side, and the infrared light shooting effect can be realized through the IR filter. The IR filter can be a visible light and infrared light waveband double-pass filter, and the imaging spectrum wavelength range is 650 nm-980 nm. The Image plane Image is an Image plane imaged behind the lens and is located at the rearmost part of the lens. Meanwhile, a diaphragm Stop is arranged in front of the lens and arranged on the front side of the first lens G1 close to the object side, and the diaphragm Stop is arranged at the foremost end of the lens, so that the diameter of the front port of the lens can be effectively reduced, and the pinhole effect is realized.

Example one

To facilitate understanding for those skilled in the art, the present invention will be described in further detail with reference to the accompanying drawings and examples.

Referring to fig. 1, a fatigue monitoring lens includes a Stop, a first lens G1, a second lens G2, a third lens G3, a fourth lens G4, and a fifth lens G5, where the Stop, the first lens G1, the second lens G2, the third lens G3, the fourth lens G4, and the fifth lens G5 are sequentially disposed from an object side to an image side; the first lens G1 is a plano-convex spherical lens, the second lens G2 is a biconcave spherical lens, the fourth lens G4 is a biconvex spherical lens, the third lens G3 and the fifth lens G5 are both meniscus spherical lenses, the third lens G3 is convex toward the image direction, and the fifth lens G5 is convex toward the object direction.

Referring to table 1, the mirror materials of the Stop, the first lens G1, the third lens G3, the fourth lens G4, and the fifth lens G5 may be made according to the parameters of table 1, and may satisfy the following requirements: the materials of the first lens G1, the third lens G3, the fourth lens G4 and the fifth lens G5 meet Nd being more than or equal to 1.70, and the material of the second lens G2 meets Vd being more than or equal to 35; the relation between the optical total length of the lens and the effective focal length value meets the condition that the ttl/f is less than or equal to 2.5; the relation between the focal length value of the second lens G2 and the effective focal length value of the lens is more than or equal to 0.5 and less than or equal to | f2/f and less than or equal to 1, and the relation between the focal length value of the third lens G3 and the effective focal length value of the lens is more than or equal to 1 and less than or equal to | f3/f and less than or equal to 2; the applicable imaging spectrum wavelength range of the lens is any wavelength between 650nm and 980nm, including visible light and infrared light bands; the angle range of the imaging field angle of the lens is 40 degrees < FOV <80 degrees, and the aperture value of the lens is F less than or equal to 2.2.

TABLE 1 mirror surface Material and Specification parameters of respective lenses

The focal length value f2 of the second lens G2 of the lens manufactured by the lens with the specification parameters and other structures is-3.85 mm, the focal length value f3 of the third lens G3 is 5.59mm, the effective focal length value f of the lens is 4.58mm, the total optical length ttl of the lens is 9.67mm, the angle of the field angle FOV of the lens is 60 degrees, the effective focal length ratio f2/f of the second lens G2 to the lens is 0.64, the effective focal length ratio f2/f of the third lens G3 to the lens is 1.22, and the ratio ttl/f of the total optical length of the lens to the effective focal length of the lens is 2.11.

Referring to fig. 2 to 5, fig. 2 is a MTF graph of the fatigue monitoring lens in the above scheme, fig. 3 is a point array graph of the fatigue monitoring lens in the above scheme, fig. 4 is a field curvature and distortion graph of the fatigue monitoring lens in the above scheme, and fig. 5 is a spherical aberration graph of the fatigue monitoring lens in the above scheme; as can be seen from fig. 2 to 5, the fatigue monitoring lens of the present embodiment has good optical performance, and meets the requirement of high resolution.

It is obvious that the above embodiments of the present invention are only examples for clearly illustrating the present invention, and are not limitations to the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A fatigue monitoring lens is characterized in that: the lens comprises a first lens (G1), a second lens (G2), a third lens (G3), a fourth lens (G4) and a fifth lens (G5), wherein the first lens (G1), the second lens (G2), the third lens (G3), the fourth lens (G4) and the fifth lens (G5) are arranged in sequence from an object side to an image side; the first lens (G1) is a plano-convex spherical lens, the second lens (G2) is a biconcave spherical lens, the fourth lens (G4) is a biconvex spherical lens, the third lens (G3) and the fifth lens (G5) are both meniscus spherical lenses, the third lens (G3) is convex to the image direction, and the fifth lens (G5) is convex to the object direction.

2. The fatigue monitoring lens of claim 1, wherein: the first lens (G1), the second lens (G2), the third lens (G3), the fourth lens (G4) and the fifth lens (G5) are all made of transparent glass materials; the materials of the first lens (G1), the third lens (G3), the fourth lens (G4) and the fifth lens (G5) all meet Nd which is more than or equal to 1.70, and the material of the second lens (G2) meets Vd which is more than or equal to 35, wherein Nd is the d-light refractive index of the lens material, and Vd is the d-light Abbe constant of the lens material.

3. The fatigue monitoring lens of claim 1, wherein: the relation between the total optical length of the lens and the effective focal length value meets the condition that the ttl/f is less than or equal to 2.5, wherein ttl is the total optical length of the lens, and f is the effective focal length value of the lens.

4. The fatigue monitoring lens of claim 1, wherein: the relation between the focal length value of the second lens (G2) and the effective focal length value of the lens meets | f2/f | of 0.5-1, wherein f2 is the focal length value of the second lens (G2), and f is the effective focal length value of the lens.

5. The fatigue monitoring lens of claim 4, wherein: the relation between the focal length value of the third lens (G3) and the effective focal length value of the lens meets | f3/f | of 1 ≦ 2, wherein f3 is the focal length value of the third lens (G3), and f is the effective focal length value of the lens.

6. The fatigue monitoring lens according to any one of claims 1 to 5, wherein: and a Stop (Stop) arranged on the front side of the first lens (G1) close to the object side.

7. The fatigue monitoring lens of claim 6, wherein: the applicable imaging spectrum wavelength range of the lens is any wavelength between 650nm and 980 nm.

8. The fatigue monitoring lens of claim 6, wherein: the angular range of the imaging field angle of the lens is 40 ° < FOV <80 °, where FOV is field angle.

9. The fatigue monitoring lens of claim 6, wherein: the aperture value of the lens is F which is not more than 2.2, wherein F is the aperture value.