CN107783258A

CN107783258A - Projection lens

Info

Publication number: CN107783258A
Application number: CN201711260269.3A
Authority: CN
Inventors: 黄林; 宋立通
Original assignee: Zhejiang Sunny Optics Co Ltd
Current assignee: Zhejiang Sunny Optics Co Ltd
Priority date: 2017-12-04
Filing date: 2017-12-04
Publication date: 2018-03-09
Anticipated expiration: 2037-12-04
Also published as: CN110208928A; CN107783258B; CN110208928B

Abstract

This application discloses a kind of projection lens, the camera lens is along optical axis by sequentially including into image side to image source side：First lens, the second lens, the 3rd lens and the 4th lens.Wherein, the first lens have positive light coke, and its image side surfaces is convex surface；Second lens have positive light coke or negative power, and its image source side surface is convex surface；3rd lens have positive light coke；And the 4th lens there is positive light coke or negative power.

Description

Projection lens

Technical field

The application is related to a kind of projection lens, more specifically, the application is related to a kind of projection lens for including four lens.

Background technology

In recent years, depth recognition technology is developed rapidly, and three-dimensional depth camera can obtain the three-dimensional of reference object Position and dimension information, this is significant in the application of AR (augmented reality) technology.

Coded structured light technology is one of most important depth recognition branch technique.Coded structured light depth recognition technology is former Reason is：It will be projected by projection lens module by the image of specific coding on reference object；Utilize an imaging receiver module To receive the pattern-information reflected；And handle to obtain the depth information of reference object by back-end algorithm.Projection lens As the core parts of coded structured light depth recognition technology, identification range and the degree of accuracy of depth recognition directly affects.

Therefore, the present invention is intended to provide a kind of have big visual field, the projection lens of miniaturization feature, preferably to meet depth The application demand of degree identification projection lens.

The content of the invention

This application provides be applicable to portable type electronic product, can at least solve or part solve it is of the prior art The projection lens of above-mentioned at least one shortcoming.

On the one hand, this application provides such a projection lens, the camera lens along optical axis by into image side to image source side sequentially Including：First lens, the second lens, the 3rd lens and the 4th lens.Wherein, the first lens can have positive light coke, and it is imaged Side surface can be convex surface；Second lens have positive light coke or negative power, and its image source side surface can be convex surface；3rd lens can With positive light coke；And the 4th lens there is positive light coke or negative power.

In one embodiment, the optics total length TTL and picture of the maximum incident angle degree CRA of chief ray, projection lens 0 ＜ (1+TAN (CRA)) * TTL/IH ＜ 2.5 can be met between the half IH of source region diagonal line length.

In one embodiment, the maximum angle of half field-of view HFOV of projection lens can meet 0.9 ＜ TAN (HFOV) ＜ 1.2.

In one embodiment, in 800nm to 1000nm light-wave band, the light penetration of projection lens can be big In 85%.

In one embodiment, the effective focal length f1 of the first lens and the effective focal length f2 of the second lens can meet 2.0 ＜ | f1/f2 | ＜ 2.8.

In one embodiment, the lens of radius of curvature R 4 and the 3rd of the image source side surface of the second lens into image side table The radius of curvature R 5 in face can meet 0.8 ＜ R4/R5 ＜ 1.2.

In one embodiment, the image side surfaces of the 3rd lens and the intersection point of optical axis are to the 3rd lens into image side table Distance SAG31 and the image source side surface of threeth lens of the effective half bore summit in face on optical axis and the intersection point of optical axis are to the 3rd Distance SAG32 of the effective half bore summit of the image source side surface of lens on optical axis can meet 0.3 ＜ SAG31/SAG32 ＜ 0.7。

In one embodiment, the effective half bore DT11 and the first lens of the image side surfaces of the first lens image source Effective half bore DT21 of side surface can meet 0.7 ＜ DT11/DT21 ＜ 1.0.

In one embodiment, the 3rd lens in the center thickness CT3 on optical axis and the 4th lens on optical axis Heart thickness CT4 can meet 1.5 ＜ CT3/CT4 ＜ 2.5.

In one embodiment, spacing distance T12 and the second lens on optical axis of the first lens and the second lens and Spacing distance T23 of 3rd lens on optical axis can meet 0.4 ＜ T12/T23 ＜ 0.7.

On the other hand, present invention also provides such a projection lens, the camera lens is along optical axis by into image side to image source side Sequentially include：First lens, the second lens, the 3rd lens and the 4th lens.Wherein, the first lens can have positive light coke, its Image side surfaces can be convex surface；Second lens have positive light coke or negative power, and its image source side surface can be convex surface；3rd is saturating Mirror can have positive light coke；And the 4th lens there is positive light coke or negative power.Wherein, the effective focal length f1 of the first lens It can meet 2.0 ＜ with the effective focal length f2 of the second lens | f1/f2 | ＜ 2.8.

Another aspect, present invention also provides such a projection lens, the camera lens is along optical axis by into image side to image source side Sequentially include：First lens, the second lens, the 3rd lens and the 4th lens.Wherein, the first lens can have positive light coke, its Image side surfaces can be convex surface；Second lens have positive light coke or negative power, and its image source side surface can be convex surface；3rd is saturating Mirror can have positive light coke；And the 4th lens there is positive light coke or negative power.Wherein, the image side surfaces of the 3rd lens It is saturating with the distance SAG31 and the 3rd of effective half bore summits of the image side surfaces of the intersection point of optical axis to the 3rd lens on optical axis The image source side surface of mirror and the intersection point of optical axis to the image source side surface of the 3rd lens effective half bore summit on optical axis away from It can meet 0.3 ＜ SAG31/SAG32 ＜ 0.7 from SAG32.

The application employs multi-disc (for example, four) lens, by each power of lens of reasonable distribution, face type, each Spacing etc. on axle between the center thickness of mirror and each lens so that above-mentioned projection lens has miniaturization, big visual field, Gao Cheng As quality, low sensitivity, at least one beneficial effect such as depth recognition requirement can be met.

Brief description of the drawings

With reference to accompanying drawing, by the detailed description of following non-limiting embodiment, other features of the application, purpose and excellent Point will be apparent.In the accompanying drawings：

Fig. 1 shows the structural representation of the projection lens according to the embodiment of the present application 1；

Fig. 2A to Fig. 2 C respectively illustrates chromatic curve on the axle of the projection lens of embodiment 1, astigmatism curve and distortion Curve；

Fig. 3 shows the structural representation of the projection lens according to the embodiment of the present application 2；

Fig. 4 A to Fig. 4 C respectively illustrate chromatic curve on the axle of the projection lens of embodiment 2, astigmatism curve and distortion Curve；

Fig. 5 shows the structural representation of the projection lens according to the embodiment of the present application 3；

Fig. 6 A to Fig. 6 C respectively illustrate chromatic curve on the axle of the projection lens of embodiment 3, astigmatism curve and distortion Curve；

Fig. 7 shows the structural representation of the projection lens according to the embodiment of the present application 4；

Fig. 8 A to Fig. 8 C respectively illustrate chromatic curve on the axle of the projection lens of embodiment 4, astigmatism curve and distortion Curve；

Fig. 9 shows the structural representation of the projection lens according to the embodiment of the present application 5；

Figure 10 A to Figure 10 C respectively illustrate chromatic curve on the axle of the projection lens of embodiment 5, astigmatism curve and abnormal Varied curve.

Embodiment

In order to more fully understand the application, refer to the attached drawing is made into more detailed description to the various aspects of the application.Should Understand, these describe the description of the simply illustrative embodiments to the application in detail, rather than limit the application in any way Scope.In the specification, identical reference numbers identical element.Stating "and/or" includes associated institute Any and all combinations of one or more of list of items.

It should be noted that in this manual, the statement of first, second grade is only used for a feature and another feature differentiation Come, and do not indicate that any restrictions to feature.Therefore, it is discussed below in the case of without departing substantially from teachings of the present application First lens are also known as the second lens, and the second lens are also known as the first lens.

In the accompanying drawings, for convenience of description, thickness, the size and dimension of lens are somewhat exaggerated.Specifically, accompanying drawing Shown in sphere or aspherical shape be illustrated by way of example.That is, sphere or aspherical shape is not limited to accompanying drawing In the sphere that shows or aspherical shape.Accompanying drawing is merely illustrative and and non-critical drawn to scale.

Herein, near axis area refers to the region near optical axis.If lens surface is convex surface and does not define the convex surface position When putting, then it represents that the lens surface is extremely convex surface less than near axis area；If lens surface is concave surface and does not define the concave surface position When, then it represents that the lens surface is extremely concave surface less than near axis area.It is referred to as image source near the surface of image source side in each lens Side surface, it is referred to as image side surfaces near the surface into image side in each lens.

It will also be appreciated that term " comprising ", " including ", " having ", "comprising" and/or " including ", when in this theory Represent stated feature, element and/or part be present when being used in bright book, but do not preclude the presence or addition of one or more Further feature, element, part and/or combinations thereof.In addition, ought the statement of such as " ... at least one " appear in institute When after the list of row feature, whole listed feature, rather than the individual component in modification list are modified.In addition, work as description originally During the embodiment of application, represented " one or more embodiments of the application " using "available".Also, term " exemplary " It is intended to refer to example or illustration.

Unless otherwise defined, otherwise all terms (including technical terms and scientific words) used herein be respectively provided with The application one skilled in the art's is generally understood that identical implication.It will also be appreciated that term (such as in everyday words Term defined in allusion quotation) implication consistent with their implications in the context of correlation technique should be interpreted as having, and It will not explained with idealization or excessively formal sense, unless clearly so limiting herein.

It should be noted that in the case where not conflicting, the feature in embodiment and embodiment in the application can phase Mutually combination.Describe the application in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

The feature of the application, principle and other aspects are described in detail below.

Such as four lens with focal power may include according to the projection lens of the application illustrative embodiments, i.e. First lens, the second lens, the 3rd lens and the 4th lens.This four lens are along optical axis by sequentially being arranged into image side to image source side Row.

In the exemplary embodiment, the first lens can have positive light coke, and its image side surfaces can be convex surface；Second is saturating Mirror has positive light coke or negative power, and its image source side surface can be convex surface；3rd lens can have positive light coke；4th lens With positive light coke or negative power.

In the exemplary embodiment, the second lens can have positive light coke, and its image side surfaces can be concave surface.

In the exemplary embodiment, the image source side surface of the 4th lens can be concave surface.

In the exemplary embodiment, the projection lens of the application can meet the ＜ of conditional 0 (1+TAN (CRA)) * TTL/IH ＜ 2.5, wherein, CRA is the maximum incident angle degree of chief ray, and TTL is the optics total length of projection lens, and IH is image source region pair The half of linea angulata length.The optics total length of projection lens refers to from the image side surfaces of the first lens to image source face on optical axis Distance, for example, the optics total length TTL in the application can refer to from the image side surfaces of the first lens to image source face in optical axis On distance.More specifically, CRA, TTL and IH can further meet 2.0 ＜ (1+TAN (CRA)) * TTL/IH ＜ 2.5, for example, 2.12≤(1+TAN(CRA))*TTL/IH≤2.31.Meet the ＜ of conditional 0 (1+TAN (CRA)) * TTL/IH ＜ 2.5, can obtain The larger angle of visual field and shorter optics total length are obtained, to meet the needs of big depth recognition scope and projection module minimize.

In the exemplary embodiment, the projection lens of the application can meet the ＜ of conditional 2.0 | f1/f2 | ＜ 2.8, its In, f1 is the effective focal length of the first lens, and f2 is the effective focal length of the second lens.More specifically, f1 and f2 can further meet 2.29≤|f1/f2|≤2.63.Meet the ＜ of conditional 2 | f1/f2 | ＜ 2.8, system astigmatism error can be effectively eliminated, to ensure Picture matter balance on meridian and sagitta of arc both direction.

In the exemplary embodiment, the projection lens of the application can meet the ＜ R4/R5 ＜ 1.2 of conditional 0.8, wherein, R4 is the radius of curvature of the image source side surface of the second lens, and R5 is the radius of curvature of the image side surfaces of the 3rd lens.More specifically Ground, R4 and R5 can further meet 0.83≤R4/R5≤1.07.Meet the ＜ R4/R5 ＜ 1.2 of conditional 0.8, can effectively correct The curvature of field aberration of system, to ensure the equilibrium of central area and fringe region image quality.

In the exemplary embodiment, the projection lens of the application can meet the ＜ SAG31/SAG32 ＜ 0.7 of conditional 0.3, Wherein, SAG31 is the image side surfaces of the 3rd lens and the intersection point of optical axis to effective half mouthful of image side surfaces of the 3rd lens Distance of the footpath summit on optical axis, SAG32 are the image source of the image source side surface of the 3rd lens and the intersection point of optical axis to the 3rd lens Distance of the effective half bore summit of side surface on optical axis.More specifically, SAG31 and SAG32 can further meet 0.40 ＜ SAG31/SAG32 ＜ 0.60, for example, 0.50≤SAG31/SAG32≤0.53.Meet the ＜ SAG31/SAG32 ＜ of conditional 0.3 0.7, system spherical aberration can be effectively eliminated, to obtain the image of fine definition.

In the exemplary embodiment, the projection lens of the application can meet the ＜ DT11/DT21 ＜ 1.0 of conditional 0.7, its In, DT11 is effective half bore of the image side surfaces of the first lens, and DT21 is effectively the half of the image source side surface of the first lens Bore.More specifically, DT11 and DT21 can further meet 0.86≤DT11/DT21≤0.95.Meet the ＜ of conditional 0.7 DT11/DT21 ＜ 1.0, be advantageous to obtain shorter camera lens overall length, to meet camera lens small form factor requirements.

In the exemplary embodiment, the projection lens of the application can meet the ＜ CT3/CT4 ＜ 2.5 of conditional 1.5, its In, CT3 be the 3rd lens in the center thickness on optical axis, CT4 is the 4th lens in the center thickness on optical axis.More specifically, CT3 and CT4 can further meet 1.64≤CT3/CT4≤2.43.Meet the ＜ CT3/CT4 ＜ 2.5 of conditional 1.5, be advantageous to obtain The larger angle of visual field is obtained, and ensures higher image quality.

In the exemplary embodiment, the projection lens of the application can meet the ＜ T12/T23 ＜ 0.7 of conditional 0.4, its In, T12 is the spacing distance of the first lens and the second lens on optical axis, and T23 is the second lens and the 3rd lens on optical axis Spacing distance.More specifically, T12 and T23 can further meet 0.56≤T12/T23≤0.62.Meet the ＜ of conditional 0.4 T12/T23 ＜ 0.7, the tolerance sensitivity of camera lens is advantageously reduced, to meet the requirement of camera lens machinability.

In the exemplary embodiment, the projection lens of the application in about 800nm into about 1000nm light-wave band, light Line transmitance is more than 85%.It is such to be provided with beneficial to the projected picture for obtaining high brightness, and reduce the aperture to projection lens It is required that.

In the exemplary embodiment, the projection lens of the application can meet conditional 0.9 ＜ TAN (HFOV) ＜ 1.2, its In, HFOV is the maximum angle of half field-of view of projection lens.More specifically, HFOV can further meet 0.95≤TAN (HFOV)≤ 1.04.Meet conditional 0.9 ＜ TAN (HFOV) ＜ 1.2, the requirement of depth recognition regional extent can be met, and keep higher Accuracy of identification.

In the exemplary embodiment, above-mentioned projection lens may also include at least one diaphragm, to lift the imaging of camera lens Quality.Diaphragm can be arranged as required to locate at an arbitrary position, for example, diaphragm may be provided at between image side and the first lens.

Alternatively, above-mentioned projection lens may also include other known optical projection elements, for example, prism, field lens etc..

Compared to common lens, the projection lens main distinction is, the light of general pick-up lens is from thing side into image side Form an image planes；And the light of general projection lens is from image source side into image side, by image planes enlarging projection until perspective plane.One As the light-inletting quantity of projection lens controlled by object-side numerical aperture and camera lens diaphragm.

Such as four lens can be used according to the projection lens of the above-mentioned embodiment of the application, it is each by reasonable distribution Spacing etc. on axle between the focal power of mirror, face type, the center thickness of each lens and each lens so that projection lens has small Type, big visual field, hyposensitivity, high image quality, at least one beneficial effect such as depth recognition requirement can be met.

In presently filed embodiment, at least one in the minute surface of each lens is aspherical mirror.Non-spherical lens The characteristics of be：From lens centre to lens perimeter, curvature is consecutive variations.It is constant with having from lens centre to lens perimeter The spherical lens of curvature is different, and non-spherical lens has more preferably radius of curvature characteristic, and there is improvement to distort aberration and improve picture The advantages of dissipating aberration.After non-spherical lens, the aberration occurred when imaging can be eliminated as much as possible, so as to improve Image quality.

However, it will be understood by those of skill in the art that without departing from this application claims technical scheme situation Under, the lens numbers for forming projection lens can be changed, to obtain each result and advantage described in this specification.Though for example, So it is described in embodiments by taking four lens as an example, but the projection lens is not limited to include four lens.If Need, the projection lens may also include the lens of other quantity.

The specific embodiment for the projection lens for being applicable to above-mentioned embodiment is further described with reference to the accompanying drawings.

Embodiment 1

Projection lens referring to Fig. 1 to Fig. 2 C descriptions according to the embodiment of the present application 1.Fig. 1 is shown according to the application The structural representation of the projection lens of embodiment 1.

As shown in figure 1, according to the projection lens of the application illustrative embodiments along optical axis by into image side to image source side according to Sequence includes：Diaphragm STO, the first lens E1, the second lens E2, the 3rd lens E3 and the 4th lens E4.

First lens E1 has positive light coke, and its image side surfaces S1 is convex surface, and image source side surface S2 is concave surface；Second is saturating Mirror E2 has positive light coke, and its image side surfaces S3 is concave surface, and image source side surface S4 is convex surface；3rd lens E3 has positive light focus Degree, its image side surfaces S5 is concave surface, and image source side surface S6 is convex surface；And the 4th lens E4 there is negative power, its be imaged Side surface S7 is convex surface, and image source side surface S8 is concave surface.S9 can be image source face, and the light from projection lens image source face is sequentially worn Cross each surface S8 to S1 and be ultimately imaged the (not shown) on screen.

In about 800nm into about 1000nm light-wave bands, the light penetration of the projection lens is more than 85%.

Table 1 shows surface type, radius of curvature, thickness, material and the circular cone of each lens of the projection lens of embodiment 1 Coefficient, wherein, the unit of radius of curvature and thickness is millimeter (mm).

Table 1

As shown in Table 1, the image side surfaces of any one lens in the first lens E1 to the 4th lens E4 and image source side Surface is aspherical.In the present embodiment, the face type x of each non-spherical lens is available but is not limited to following aspherical formula and enters Row limits：

Wherein, x be it is aspherical along optical axis direction when being highly h position, away from aspheric vertex of surface apart from rise；C is Aspherical paraxial curvature, c=1/R (that is, paraxial curvature c is the mean curvature radius R of upper table 1 inverse)；K be circular cone coefficient ( Provided in table 1)；Ai is the correction factor of aspherical i-th-th ranks.Table 2 below is given available for each aspherical in embodiment 1 Minute surface S1-S8 high order term coefficient A₄、A₆、A₈、A₁₀、A₁₂、A₁₄And A₁₆。

Face number

A4

A6

A8

A10

A12

A14

A16

S1

1.5615E-01

-4.1916E+00

1.0055E+02

-1.0841E+03

5.7844E+03

-1.4246E+04

1.2976E+04

S2

4.9464E-01

6.9931E-01

1.4940E+01

-1.8713E+02

1.8504E+03

-8.8115E+03

1.9038E+04

S3

-4.1066E-01

-2.8918E+01

5.3999E+02

-5.5399E+03

2.9869E+04

-8.1639E+04

9.0669E+04

S4

-2.8917E-01

7.5873E+00

-9.6838E+01

6.3678E+02

-2.2453E+03

3.9455E+03

-2.6261E+03

S5

-3.7771E-01

-1.0334E+00

6.5029E+00

-1.0025E+01

7.1543E+00

-2.4772E+00

3.3604E-01

S6

-1.1253E+00

4.5667E+00

-1.0239E+01

1.3167E+01

-8.9996E+00

3.0492E+00

-4.0198E-01

S7

-1.5132E+00

1.9426E+00

-9.7812E-01

6.1994E-02

1.5356E-01

-6.4488E-02

8.2865E-03

S8

-4.8483E-01

3.1658E-02

3.9269E-01

-4.0333E-01

1.9364E-01

-4.5723E-02

4.1905E-03

Table 2

Table 3 provides the optics total length TTL of projection lens in embodiment 1 (that is, from the first lens E1 image side surfaces S1 To distances of the image source face S9 on optical axis), maximum angle of half field-of view HFOV, the effective focal length f1 of total effective focal length f and each lens To f4.

Table 3

Projection lens in embodiment 1 meets：

(1+TAN (CRA)) * TTL/IH=2.12, wherein, CRA is the maximum incident angle degree of chief ray, and TTL is projection lens The optics total length of head, IH are the half of image source region diagonal line length；

| f1/f2 |=2.43, wherein, f1 is the first lens E1 effective focal length, and f2 is the second lens E2 effective focal length；

R4/R5=0.98, wherein, R4 is the second lens E2 image source side surface S4 radius of curvature, and R5 is the 3rd lens E3 image side surfaces S5 radius of curvature；

SAG31/SAG32=0.50, wherein, the image side surfaces S5 and the intersection point of optical axis that SAG31 is the 3rd lens E3 are extremely Distance of the 3rd lens E3 image side surfaces S5 effective half bore summit on optical axis, SAG32 are the 3rd lens E3 picture The intersection point of source surface S6 and optical axis to the 3rd lens E3 image source side surface S6 effective half bore summit on optical axis away from From；

DT11/DT21=0.89, wherein, DT11 be the first lens E1 image side surfaces S1 effective half bore, DT21 For the first lens E1 image source side surface S2 effective half bore；

CT3/CT4=1.94, wherein, CT3 be the 3rd lens E3 in the center thickness on optical axis, CT4 is the 4th lens E4 In the center thickness on optical axis；

T12/T23=0.56, wherein, T12 is the spacing distance of the first lens E1 and the second lens E2 on optical axis, T23 For the spacing distance of the second lens E2 and the 3rd lens E3 on optical axis；

TAN (HFOV)=1.04, wherein, HFOV is the maximum angle of half field-of view of projection lens.

Fig. 2A shows chromatic curve on the axle of the projection lens of embodiment 1, and it represents the light of different wave length via mirror Converging focal point after head deviates.Fig. 2 B show the astigmatism curve of the projection lens of embodiment 1, its represent meridianal image surface bending and Sagittal image surface is bent.Fig. 2 C show the distortion curve of the projection lens of embodiment 1, and it represents the distortion in the case of different visual angles Sizes values.Understand that the projection lens given by embodiment 1 can realize good image quality according to Fig. 2A to Fig. 2 C.

Embodiment 2

Projection lens referring to Fig. 3 to Fig. 4 C descriptions according to the embodiment of the present application 2.In the present embodiment and following implementation In example, for brevity, by clipped description similar to Example 1.Fig. 3 shows the throwing according to the embodiment of the present application 2 The structural representation of shadow camera lens.

As shown in figure 3, according to the projection lens of the application illustrative embodiments along optical axis by into image side to image source side according to Sequence includes：Diaphragm STO, the first lens E1, the second lens E2, the 3rd lens E3 and the 4th lens E4.

Table 4 shows surface type, radius of curvature, thickness, material and the circular cone of each lens of the projection lens of embodiment 2 Coefficient, wherein, the unit of radius of curvature and thickness is millimeter (mm).

Table 4

As shown in Table 4, in example 2, any one lens in the first lens E1 to the 4th lens E4 into image side Surface and image source side surface are aspherical.Table 5 shows the high order term coefficient available for each aspherical mirror in embodiment 2, Wherein, each aspherical face type can be limited by the formula (1) provided in above-described embodiment 1.

Table 5

Table 6 provides the optics total length TTL, maximum angle of half field-of view HFOV, total effective focal length f of projection lens in embodiment 2 And the effective focal length f1 to f4 of each lens.

Table 6

Fig. 4 A show chromatic curve on the axle of the projection lens of embodiment 2, and it represents the light of different wave length via mirror Converging focal point after head deviates.Fig. 4 B show the astigmatism curve of the projection lens of embodiment 2, its represent meridianal image surface bending and Sagittal image surface is bent.Fig. 4 C show the distortion curve of the projection lens of embodiment 2, and it represents the distortion in the case of different visual angles Sizes values.Understand that the projection lens given by embodiment 2 can realize good image quality according to Fig. 4 A to Fig. 4 C.

Embodiment 3

The projection lens according to the embodiment of the present application 3 is described referring to Fig. 5 to Fig. 6 C.Fig. 5 is shown according to this Shen Please embodiment 3 projection lens structural representation.

As shown in figure 5, according to the projection lens of the application illustrative embodiments along optical axis by into image side to image source side according to Sequence includes：Diaphragm STO, the first lens E1, the second lens E2, the 3rd lens E3 and the 4th lens E4.

First lens E1 has positive light coke, and its image side surfaces S1 is convex surface, and image source side surface S2 is concave surface；Second is saturating Mirror E2 has positive light coke, and its image side surfaces S3 is concave surface, and image source side surface S4 is convex surface；3rd lens E3 has positive light focus Degree, its image side surfaces S5 is concave surface, and image source side surface S6 is convex surface；And the 4th lens E4 there is negative power, its be imaged Side surface S7 is concave surface, and image source side surface S8 is concave surface.S9 can be image source face, and the light from projection lens image source face is sequentially worn Cross each surface S8 to S1 and be ultimately imaged the (not shown) on screen.

Table 7 shows surface type, radius of curvature, thickness, material and the circular cone of each lens of the projection lens of embodiment 3 Coefficient, wherein, the unit of radius of curvature and thickness is millimeter (mm).

Table 7

As shown in Table 7, in embodiment 3, any one lens in the first lens E1 to the 4th lens E4 into image side Surface and image source side surface are aspherical.Table 5 shows the high order term coefficient available for each aspherical mirror in embodiment 2, Wherein, each aspherical face type can be limited by the formula (1) provided in above-described embodiment 1.

Face number

A4

A6

A8

A10

A12

A14

A16

S1

3.6418E-01

-4.2484E+00

1.7253E+02

-7.6872E+02

-1.3616E+04

1.5380E+05

-4.3657E+05

S2

2.7243E-01

3.4752E+00

-6.0200E+01

6.5103E+02

-1.5180E+03

-1.2495E+03

0.0000E+00

S3

-5.1748E-01

-2.9525E+01

5.3533E+02

-5.5151E+03

3.0152E+04

-7.9913E+04

9.7487E+04

S4

-2.1095E-01

7.5296E+00

-9.7206E+01

6.3590E+02

-2.2444E+03

3.9587E+03

-2.6054E+03

S5

-2.7582E-01

-1.0365E+00

6.4469E+00

-1.0020E+01

7.1576E+00

-2.4712E+00

3.4350E-01

S6

-1.0491E+00

4.4781E+00

-1.0164E+01

1.3186E+01

-9.0173E+00

3.0361E+00

-3.9036E-01

S7

-1.4776E+00

1.9597E+00

-9.8528E-01

6.4358E-02

1.5180E-01

-6.3891E-02

8.2018E-03

S8

-4.8982E-01

2.9768E-02

4.0658E-01

-4.0842E-01

1.9888E-01

-4.8349E-02

4.3821E-03

Table 8

Table 9 provides the optics total length TTL, maximum angle of half field-of view HFOV, total effective focal length f of projection lens in embodiment 3 And the effective focal length f1 to f4 of each lens.

Table 9

Fig. 6 A show chromatic curve on the axle of the projection lens of embodiment 3, and it represents the light of different wave length via mirror Converging focal point after head deviates.Fig. 6 B show the astigmatism curve of the projection lens of embodiment 3, its represent meridianal image surface bending and Sagittal image surface is bent.Fig. 6 C show the distortion curve of the projection lens of embodiment 3, and it represents the distortion in the case of different visual angles Sizes values.Understand that the projection lens given by embodiment 3 can realize good image quality according to Fig. 6 A to Fig. 6 C.

Embodiment 4

The projection lens according to the embodiment of the present application 4 is described referring to Fig. 7 to Fig. 8 C.Fig. 7 is shown according to this Shen Please embodiment 4 projection lens structural representation.

As shown in fig. 7, according to the projection lens of the application illustrative embodiments along optical axis by into image side to image source side according to Sequence includes：Diaphragm STO, the first lens E1, the second lens E2, the 3rd lens E3 and the 4th lens E4.

Table 10 shows surface type, radius of curvature, thickness, material and the circle of each lens of the projection lens of embodiment 4 Coefficient is bored, wherein, the unit of radius of curvature and thickness is millimeter (mm).

Table 10

As shown in Table 10, in example 4, any one lens in the first lens E1 to the 4th lens E4 into image side Surface and image source side surface are aspherical.Table 11 shows the high order term coefficient available for each aspherical mirror in embodiment 4, Wherein, each aspherical face type can be limited by the formula (1) provided in above-described embodiment 1.

Face number

A4

A6

A8

A10

A12

A14

A16

S1

5.3149E-01

-8.3884E+00

1.7885E+02

-7.5712E+02

-1.3476E+04

1.5316E+05

-4.4688E+05

S2

3.6122E-02

5.7148E+00

-8.0089E+01

5.7882E+02

-1.6399E+03

3.7888E+02

0.0000E+00

S3

-3.1367E-01

-2.8910E+01

5.4553E+02

-5.5178E+03

2.9882E+04

-8.1978E+04

8.7675E+04

S4

-9.0248E-02

7.2188E+00

-9.6116E+01

6.3941E+02

-2.2421E+03

3.9436E+03

-2.6396E+03

S5

-3.7940E-01

-1.0355E+00

6.5031E+00

-1.0026E+01

7.1514E+00

-2.4784E+00

3.3924E-01

S6

-1.1388E+00

4.5679E+00

-1.0241E+01

1.3165E+01

-9.0009E+00

3.0484E+00

-4.0259E-01

S7

-1.5062E+00

1.9490E+00

-9.7977E-01

6.5003E-02

1.5082E-01

-6.3256E-02

8.1176E-03

S8

-4.9308E-01

2.9134E-02

4.0407E-01

-4.0863E-01

1.9907E-01

-4.8110E-02

4.5562E-03

Table 11

Table 12 provides the optics total length TTL, maximum angle of half field-of view HFOV, total effective focal length f of projection lens in embodiment 4 And the effective focal length f1 to f4 of each lens.

Table 12

Fig. 8 A show chromatic curve on the axle of the projection lens of embodiment 4, and it represents the light of different wave length via mirror Converging focal point after head deviates.Fig. 8 B show the astigmatism curve of the projection lens of embodiment 4, its represent meridianal image surface bending and Sagittal image surface is bent.Fig. 8 C show the distortion curve of the projection lens of embodiment 4, and it represents the distortion in the case of different visual angles Sizes values.Understand that the projection lens given by embodiment 4 can realize good image quality according to Fig. 8 A to Fig. 8 C.

Embodiment 5

The projection lens according to the embodiment of the present application 5 is described referring to Fig. 9 to Figure 10 C.Fig. 9 is shown according to this Shen Please embodiment 5 projection lens structural representation.

As shown in figure 9, according to the projection lens of the application illustrative embodiments along optical axis by into image side to image source side according to Sequence includes：Diaphragm STO, the first lens E1, the second lens E2, the 3rd lens E3 and the 4th lens E4.

First lens E1 has positive light coke, and its image side surfaces S1 is convex surface, and image source side surface S2 is concave surface；Second is saturating Mirror E2 has positive light coke, and its image side surfaces S3 is concave surface, and image source side surface S4 is convex surface；3rd lens E3 has positive light focus Degree, its image side surfaces S5 is concave surface, and image source side surface S6 is convex surface；And the 4th lens E4 there is positive light coke, its be imaged Side surface S7 is convex surface, and image source side surface S8 is concave surface.S9 can be image source face, and the light from projection lens image source face is sequentially worn Cross each surface S8 to S1 and be ultimately imaged the (not shown) on screen.

Table 13 shows surface type, radius of curvature, thickness, material and the circle of each lens of the projection lens of embodiment 5 Coefficient is bored, wherein, the unit of radius of curvature and thickness is millimeter (mm).

Table 13

As shown in Table 13, in embodiment 5, any one lens in the first lens E1 to the 4th lens E4 into image side Surface and image source side surface are aspherical.Table 14 shows the high order term coefficient available for each aspherical mirror in embodiment 5, Wherein, each aspherical face type can be limited by the formula (1) provided in above-described embodiment 1.

Face number

A4

A6

A8

A10

A12

A14

A16

S1

5.0519E-01

-8.6079E+00

1.8062E+02

-7.2450E+02

-1.3482E+04

1.5082E+05

-4.3927E+05

S2

-9.8834E-03

5.8792E+00

-7.5804E+01

5.7759E+02

-1.9467E+03

2.1590E+03

0.0000E+00

S3

-3.1328E-01

-2.9784E+01

5.4264E+02

-5.5215E+03

2.9905E+04

-8.1677E+04

9.0278E+04

S4

-9.1581E-02

7.0852E+00

-9.6316E+01

6.3912E+02

-2.2428E+03

3.9412E+03

-2.6493E+03

S5

-3.7945E-01

-1.0358E+00

6.5023E+00

-1.0028E+01

7.1498E+00

-2.4795E+00

3.4191E-01

S6

-1.1307E+00

4.5723E+00

-1.0240E+01

1.3165E+01

-9.0007E+00

3.0486E+00

-4.0225E-01

S7

-1.5099E+00

1.9490E+00

-9.7984E-01

6.4954E-02

1.5081E-01

-6.3254E-02

8.1228E-03

S8

-4.8520E-01

2.9035E-02

4.0341E-01

-4.0887E-01

1.9901E-01

-4.8124E-02

4.5537E-03

Table 14

Table 15 provides the optics total length TTL, maximum angle of half field-of view HFOV, total effective focal length f of projection lens in embodiment 5 And the effective focal length f1 to f4 of each lens.

Table 15

Figure 10 A show chromatic curve on the axle of the projection lens of embodiment 5, and it represents the light of different wave length via mirror Converging focal point after head deviates.Figure 10 B show the astigmatism curve of the projection lens of embodiment 5, and it represents meridianal image surface bending Bent with sagittal image surface.Figure 10 C show the distortion curve of the projection lens of embodiment 5, and it is represented in the case of different visual angles Distort sizes values.Understand that the projection lens given by embodiment 5 can realize good imaging product according to Figure 10 A to Figure 10 C Matter.

To sum up, embodiment 1 to embodiment 5 meets the relation shown in table 16 respectively.

Table 16

Above description is only the preferred embodiment of the application and the explanation to institute's application technology principle.People in the art Member should be appreciated that invention scope involved in the application, however it is not limited to the technology that the particular combination of above-mentioned technical characteristic forms Scheme, while should also cover in the case where not departing from the inventive concept, carried out by above-mentioned technical characteristic or its equivalent feature The other technical schemes for being combined and being formed.Such as features described above has similar work(with (but not limited to) disclosed herein The technical scheme that the technical characteristic of energy is replaced mutually and formed.

Claims

1. projection lens, along optical axis by sequentially including into image side to image source side：First lens, the second lens, the 3rd lens and Four lens, it is characterised in that

First lens have positive light coke, and its image side surfaces is convex surface；

Second lens have positive light coke or negative power, and its image source side surface is convex surface；

3rd lens have positive light coke；And

4th lens have positive light coke or negative power.

2. projection lens according to claim 1, it is characterised in that meet 0 ＜ (1+TAN (CRA)) * TTL/IH ＜ 2.5,

Wherein, CRA is the maximum incident angle degree of chief ray, and TTL is the optics total length of projection lens, and IH is that image source region is diagonal The half of line length.

3. projection lens according to claim 1, it is characterised in that the maximum angle of half field-of view HFOV of the projection lens expires 0.9 ＜ TAN (HFOV) ＜ 1.2 of foot.

4. projection lens according to claim 1, it is characterised in that described in 800nm to 1000nm light-wave band The light penetration of projection lens is more than 85%.

5. the projection lens according to any one of claim 2 to 4, it is characterised in that effective Jiao of first lens Effective focal length f2 away from f1 and second lens meets 2.0 ＜ | f1/f2 | ＜ 2.8.

6. projection lens according to any one of claim 1 to 4, it is characterised in that the image source side of second lens The radius of curvature R 4 on surface and the radius of curvature R 5 of the image side surfaces of the 3rd lens meet 0.8 ＜ R4/R5 ＜ 1.2.

7. projection lens according to any one of claim 1 to 4, it is characterised in that meet 0.3 ＜ SAG31/SAG32 ＜ 0.7,

Wherein, SAG31 is the imaging of the image side surfaces of the 3rd lens and the intersection point of the optical axis to the 3rd lens Distance of the effective half bore summit of side surface on the optical axis, image source side surfaces and institute of the SAG32 for the 3rd lens State the distance of the intersection point of optical axis to effective half bore summit of the image source side surface of the 3rd lens on the optical axis.

8. projection lens according to any one of claim 1 to 4, it is characterised in that first lens into image side Effective half bore DT11 on surface and effective half bore DT21 of the image source side surface of first lens meet 0.7 ＜ DT11/ DT21 ＜ 1.0.

9. projection lens according to any one of claim 1 to 4, it is characterised in that the 3rd lens are in the light Center thickness CT3 on axle meets 1.5 ＜ CT3/CT4 ＜ with the 4th lens in the center thickness CT4 on the optical axis 2.5。

10. projection lens according to any one of claim 1 to 4, it is characterised in that first lens and described Spacing distance T12 of two lens on the optical axis and the interval of second lens and the 3rd lens on the optical axis Distance T23 meets 0.4 ＜ T12/T23 ＜ 0.7.

11. projection lens, along optical axis by sequentially including into image side to image source side：First lens, the second lens, the 3rd lens and Four lens, it is characterised in that

3rd lens have positive light coke；

4th lens have positive light coke or negative power；And

Wherein, the effective focal length f1 of first lens and second lens effective focal length f2 meet 2.0 ＜ | f1/f2 | ＜ 2.8。