CN113835203A - Large-light-transmission high-illumination projection lens matched with 0.47DMD - Google Patents

Abstract

The invention discloses a large-light-passing high-illumination projection lens matched with a 0.47DMD, which sequentially comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a diaphragm, a sixth lens, a seventh lens, an eighth lens, a ninth lens and a tenth lens from an object side to an image side along an optical axis, wherein the first lens to the tenth lens respectively comprise an object side surface and an image side surface; the first lens element has a negative refractive index, the second lens element has a negative refractive index, the third lens element has a positive refractive index, the fourth lens element has a negative refractive index, the fifth lens element has a positive refractive index, the sixth lens element has a negative refractive index, the seventh lens element has a negative refractive index, the eighth lens element has a positive refractive index, the ninth lens element has a negative refractive index, the tenth lens element has a positive refractive index, and only ten lens elements having refractive indices are provided in the optical imaging lens assembly. The actual maximum compatible target surface size of the invention can reach phi 16mm, and the invention has strong compatible use characteristics; the projected picture is clear and uniform by adopting a large-aperture high-illumination design.

Description

Large-light-transmission high-illumination projection lens matched with 0.47DMD

Technical Field

The invention relates to the technical field of lenses, in particular to a high-light-transmission and high-illumination projection lens matched with 0.47DMD

Background

In projection equipment (such as a film projector, a laser projection television and the like), a projection display part of the projection equipment consists of a laser light source, a light processing part (namely an optical machine part) and a lens, wherein the laser light source is used for forming three primary colors or four primary colors to provide illumination for the optical machine part, and the three primary colors or the four primary colors enter the optical machine part in sequence, are modulated by a DMD (Digital Micro-mirror Device) chip and output to the laser projection lens part, and are projected onto a projection screen through an optical system of the laser projection lens to display images.

Projection lenses are an important component of projection equipment, but the existing projection lenses have at least the following defects: the matching target surface is usually not large, the projection picture is small, and the application range is limited; generally, the brightness uniformity of the projected picture is poor due to small light passing or insufficient edge relative illumination; most of the devices do not have the temperature drift characteristic, and if the brightness of the optical machine is too high or the working time is too long in actual use, the phenomenon of thermal defocusing can occur, so that the actual use is influenced.

Disclosure of Invention

The present invention is directed to a high-throughput high-illumination projection lens with a 0.47DMD, so as to solve at least one of the above problems.

In order to achieve the purpose, the invention adopts the following technical scheme:

a large-light-passing high-illumination projection lens matched with a 0.47DMD sequentially comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a diaphragm, a sixth lens, a seventh lens, an eighth lens, a ninth lens and a tenth lens from an object side to an image side along an optical axis, wherein the first lens to the tenth lens respectively comprise an object side surface facing to the object side and enabling imaging light rays to pass and an image side surface facing to the image side and enabling the imaging light rays to pass;

the first lens element with negative refractive index has a convex object-side surface and a concave image-side surface;

the second lens element with negative refractive index has a convex object-side surface and a concave image-side surface;

the third lens element with positive refractive index has a concave object-side surface and a convex image-side surface;

the fourth lens element has a negative refractive index, and has a concave object-side surface and a planar image-side surface;

the fifth lens element with positive refractive index has a convex object-side surface and a convex image-side surface;

the sixth lens element with negative refractive index has a convex object-side surface and a concave image-side surface;

the seventh lens element with negative refractive index has a concave object-side surface or a plane surface and a concave image-side surface;

the eighth lens element with a positive refractive index has a convex object-side surface and a convex image-side surface;

the ninth lens element with negative refractive index has a concave object-side surface and a convex image-side surface;

the tenth lens element with a positive refractive index has a convex object-side surface and a convex image-side surface;

the optical imaging lens has only ten lenses with refractive indexes.

Preferably, the second lens adopts a plastic high-order even-order aspheric lens.

Preferably, the tenth lens is a glass high-order even-order aspheric lens.

Preferably, the first lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens and the ninth lens are all glass spherical lenses, wherein the eighth lens is made of a material with a negative temperature coefficient of refractive index dn/dt.

Preferably, the lens complies with the following conditional expression:

-4.0＜(f1/f)＜-3.0，3.0＜(f3/f)＜-4.0，-7.5＜(f4/f)＜-5.5，

2.5＜(f5/f)＜3.5，-4.5＜(f6/f)＜-3.0，-5.5＜(f7/f)＜-3.5，

1.5＜(f8/f)＜2.5，-5＜(f9/f)＜-3.0，

wherein f is a focal length value of the lens, and f1, f3, f4, f5, f6, f7, f8 and f9 are focal length values of the first lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens and the ninth lens, respectively.

Preferably, the image-side surface of the eighth lens element and the object-side surface of the ninth lens element are cemented to each other, and the following conditional expressions are satisfied: vd8 is more than 70, Vd9 is less than 35, wherein, Vd8 is the abbe number of the eighth lens, and Vd9 is the abbe number of the ninth lens.

Preferably, the effective aperture of the first lens is D1, D1 < phi 36.00 mm.

Preferably, the lens complies with the following conditional expression:

10.2＜TTL/f＜10.6,3.0＜BFL/f＜3.6,

wherein, TTL is the distance on the optical axis from the object-side surface of the first lens element to the imaging surface, BFL is the distance from the tenth lens element of the lens element to the DMD surface, and f is the focal length of the lens element.

After adopting the technical scheme, compared with the background technology, the invention has the following advantages:

1. the invention adopts ten lenses along the direction from the object side to the image side, and through the arrangement design of the refractive index and the surface type of each lens, the lens is matched with a 0.47' DMD chip, and the design of 100% offset is adopted, the actual maximum compatible target surface size can reach phi 16mm, and the invention has strong compatible use characteristics.

2. The invention adopts a large-aperture high-illumination design, the light transmission F/1.7 is designed, the relative illumination of 16mm at the edge phi is more than 65%, and the optical MTF values are all more than 0.3 at 93lp/mm, so that the projected picture is clear and uniform, and the common problems of a projection lens, such as smear, uneven picture image quality and the like, can not occur.

3. The invention strictly controls the distortion, controls the optical distortion within +/-0.5 percent, ensures that the projection picture does not generate obvious deformation, adopts achromatic design, ensures that the vertical axis chromatic aberration of the lens is less than 5um, and ensures that the blue edge or red edge of the projection picture does not occur.

4. The second lens and the tenth lens both adopt aspheric lenses, so that high-order aberration of the traditional large-aperture projection lens can be corrected, projected images of the lens are clear and uniform, and the effects of correcting distortion and improving resolution are achieved.

5. The invention improves the heat defocusing phenomenon of the traditional projection lens, greatly improves the temperature drift characteristic of the lens by adopting the measures of preposing the second lens, adopting the eighth lens with the refractive index temperature coefficient dn/dt as a negative value and the like, and can ensure that the picture is clear and not defocused when the lens is used in a temperature range of-10 ℃ to 65 ℃.

Drawings

FIG. 1 is a light path diagram according to the first embodiment;

FIG. 2 is a graph of MTF of a lens in 460nm-620nm in visible light according to an embodiment;

FIG. 3 is a defocus graph of the lens in the first embodiment under 460nm-620nm visible light;

FIG. 4 is a lateral chromatic aberration curve of the lens in 460nm-620nm of visible light according to the first embodiment;

FIG. 5 is a graph of field curvature and distortion under 460nm-620nm in visible light for a lens according to an embodiment;

FIG. 6 is a graph of relative illumination at 620nm for a lens according to one embodiment;

FIG. 7 is a light path diagram of the second embodiment;

FIG. 8 is a graph of MTF of the lens of the second embodiment in the visible light range of 460nm to 620 nm;

FIG. 9 is a defocus graph of the lens in the second embodiment in the visible light range of 460nm-620 nm;

FIG. 10 is a lateral chromatic aberration curve of the lens of the second embodiment under the visible light of 460nm-620 nm;

FIG. 11 is a graph of curvature of field and distortion under 460nm-620nm in the visible light of the lens of the second embodiment;

FIG. 12 is a graph of relative illumination at 620nm for a lens of the second embodiment;

FIG. 13 is a light path diagram of the third embodiment;

FIG. 14 is a graph of MTF of a lens of the third embodiment in the visible range of 460nm-620 nm;

FIG. 15 is a defocus graph of the lens in the third embodiment in the visible light range of 460nm-620 nm;

FIG. 16 is a lateral chromatic aberration curve of the lens of the third embodiment under the visible light of 460nm-620 nm;

FIG. 17 is a graph of curvature of field and distortion under 460nm-620nm in the third embodiment;

FIG. 18 is a graph of relative illuminance at 620nm for a lens of the third embodiment;

FIG. 19 is a light path diagram of the fourth embodiment;

FIG. 20 is a graph of MTF of a lens of the fourth embodiment in the visible range of 460nm-620 nm;

FIG. 21 is a defocus graph of the lens in the fourth embodiment under 460nm-620nm visible light;

FIG. 22 is a lateral chromatic aberration curve of the lens of the fourth embodiment in the visible light range from 460nm to 620 nm;

FIG. 23 is a graph of curvature of field and distortion under 460nm-620nm in the visible light of the lens of the fourth embodiment;

FIG. 24 is a graph of relative illuminance at 620nm for visible light for a lens of the fourth embodiment.

Description of reference numerals:

the lens comprises a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, a seventh lens 7, an eighth lens 8, a ninth lens 9, a tenth lens 10, a diaphragm 11, a relay prism 12 and a protective glass 13.

Detailed Description

To further illustrate the various embodiments, the invention provides the accompanying drawings. The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the embodiments. Those skilled in the art will appreciate still other possible embodiments and advantages of the present invention with reference to these figures. Elements in the figures are not drawn to scale and like reference numerals are generally used to indicate like elements.

The invention will now be further described with reference to the accompanying drawings and detailed description.

In the present specification, the term "a lens element having a positive refractive index (or a negative refractive index)" means that the paraxial refractive index of the lens element calculated by the gauss theory is positive (or negative). The term "object-side (or image-side) of a lens" is defined as the specific range of imaging light rays passing through the lens surface. The determination of the surface shape of the lens can be performed by the judgment method of a person skilled in the art, i.e., by the sign of the curvature radius (abbreviated as R value). The R value may be commonly used in optical design software, such as Zemax or CodeV. The R value is also commonly found in lens data sheets (lens sheets) of optical design software. When the R value is positive, the object side is judged to be a convex surface; and when the R value is negative, judging that the object side surface is a concave surface. On the contrary, regarding the image side surface, when the R value is positive, the image side surface is judged to be a concave surface; when the R value is negative, the image side surface is judged to be convex.

The invention discloses a large-light-passing high-illumination projection lens matched with a 0.47DMD (digital micromirror device), which sequentially comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a diaphragm, a sixth lens, a seventh lens, an eighth lens, a ninth lens and a tenth lens from an object side to an image side along an optical axis, wherein the first lens to the tenth lens respectively comprise an object side surface facing the object side and allowing imaging light to pass and an image side surface facing the image side and allowing the imaging light to pass;

the first lens element with negative refractive index has a convex object-side surface and a concave image-side surface;

the second lens element with negative refractive index has a convex object-side surface and a concave image-side surface;

the third lens element with positive refractive index has a concave object-side surface and a convex image-side surface;

the fourth lens element has a negative refractive index, and has a concave object-side surface and a planar image-side surface;

the fifth lens element with positive refractive index has a convex object-side surface and a convex image-side surface;

the sixth lens element with negative refractive index has a convex object-side surface and a concave image-side surface;

the seventh lens element with negative refractive index has a concave object-side surface or a plane surface and a concave image-side surface;

the eighth lens element with a positive refractive index has a convex object-side surface and a convex image-side surface;

the ninth lens element with negative refractive index has a concave object-side surface and a convex image-side surface;

the tenth lens element with a positive refractive index has a convex object-side surface and a convex image-side surface;

the optical imaging lens only comprises the ten lenses with the refractive index, is suitable for a 0.47' DMD, adopts a 100% offset design, and has wide adjustable picture and wider application range.

Preferably, the second lens is a plastic high-order even-order aspheric lens, and the second lens can correct high-order aberration and wide beam field curvature introduced by a wide angle at the front end, and simultaneously avoids surface type change of the plastic lens caused by overhigh temperature at the rear end when the plastic lens is arranged at the rear end.

Preferably, the tenth lens is a glass high-order even-order aspheric lens, the tenth lens can correct residual aberration and field curvature of the front-end optical system at the final position, and the glass is made of high-temperature-resistant glass material, so that the influence of surface type change on the quality of a projected image is reduced when the temperature is changed sharply.

The equation for the object-side and image-side curves of an aspheric lens is expressed as follows:

wherein:

z: depth of the aspheric surface (the vertical distance between a point on the aspheric surface that is y from the optical axis and a tangent plane tangent to the vertex on the optical axis of the aspheric surface);

c: the curvature of the aspheric vertex (the vertex curvature);

k: cone coefficient (Conic Constant);

radial distance (radial distance);

r_n: normalized radius (normalysis radius (NRADIUS));

u：r/r_n；

a_m: mth order Q^conCoefficient (is the mth Q)^con coefficient)；

Q_m ^con: mth order Q^conPolynomial (the mth Q)^con polynomial)。

Preferably, the first lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens and the ninth lens are all glass spherical lenses, wherein the eighth lens is made of a material with a negative temperature coefficient of refractive index dn/dt, that is, the refractive index of the material is reduced along with the increase of temperature, and the eighth lens can offset the influence of temperature change on the back focal shift of the lens, so that the temperature drift is effectively balanced, and the thermal defocusing phenomenon is not easy to occur.

Preferably, the lens complies with the following conditional expression:

-4.0＜(f1/f)＜-3.0，3.0＜(f3/f)＜-4.0，-7.5＜(f4/f)＜-5.5，

2.5＜(f5/f)＜3.5，-4.5＜(f6/f)＜-3.0，-5.5＜(f7/f)＜-3.5，

1.5＜(f8/f)＜2.5，-5＜(f9/f)＜-3.0，

wherein f is a focal length value of the lens, and f1, f3, f4, f5, f6, f7, f8 and f9 are focal length values of the first lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens and the ninth lens, respectively.

Preferably, the image-side surface of the eighth lens element and the object-side surface of the ninth lens element are cemented to each other, and the following conditional expressions are satisfied: vd8 is more than 70, Vd9 is less than 35, wherein, Vd8 is the abbe number of the eighth lens, and Vd9 is the abbe number of the ninth lens.

Preferably, the effective aperture of the first lens is D1, D1 < phi 36.00 mm.

Preferably, the lens complies with the following conditional expression:

10.2＜TTL/f＜10.6,3.0＜BFL/f＜3.6,

wherein, TTL is the distance on the optical axis from the object-side surface of the first lens element to the imaging surface, BFL is the distance from the tenth lens element of the lens element to the DMD surface, and f is the focal length of the lens element.

The projection lens of the present invention will be described in detail with specific embodiments.

Example one

Referring to fig. 1, the present embodiment discloses a large-pass high-illuminance projection lens with a 0.47DMD, which includes, in order along an optical axis from an object side a1 to an image side a2, a first lens element 1, a second lens element 2, a third lens element 3, a fourth lens element 4, a fifth lens element 5, a stop 11, a sixth lens element 6, a seventh lens element 7, an eighth lens element 8, a ninth lens element 9, and a tenth lens element 10, wherein each of the first lens element 1 to the tenth lens element 10 includes an object-side surface facing to the object side a1 and allowing passage of imaging light, and an image-side surface facing to the image side a2 and allowing passage of imaging light;

the first lens element 1 has a negative refractive index, and the object-side surface and the image-side surface of the first lens element 1 are convex and concave;

the second lens element 2 has a negative refractive index, and the object-side surface and the image-side surface of the second lens element 2 are convex and concave;

the third lens element 3 has a positive refractive index, and the object-side surface and the image-side surface of the third lens element 3 are concave and convex respectively;

the fourth lens element 4 has a negative refractive index, and the object-side surface and the image-side surface of the fourth lens element 4 are concave and planar;

the fifth lens element 5 has a positive refractive index, and the object-side surface and the image-side surface of the fifth lens element 5 are convex and convex;

the sixth lens element 6 has a negative refractive index, and the sixth lens element 6 has a convex object-side surface and a concave image-side surface;

the seventh lens element 7 has a negative refractive index, and the seventh lens element 7 has a concave object-side surface or a flat surface and a concave image-side surface;

the eighth lens element 8 has a positive refractive index, and the eighth lens element 8 has a convex object-side surface and a convex image-side surface;

the ninth lens element 9 has a negative refractive index, and the ninth lens element 9 has a concave object-side surface and a convex image-side surface;

the tenth lens element 10 with positive refractive index has a convex object-side surface and a convex image-side surface, and the tenth lens element 10 is disposed on the object-side surface and the image-side surface;

the optical imaging lens only has the ten lenses with the refractive index; the second lens 2 is a plastic high-order even-order aspheric lens, the tenth lens 10 is a glass high-order even-order aspheric lens, and the first lens 1, the third lens 3, the fourth lens 4, the fifth lens 5, the sixth lens 6, the seventh lens 7, the eighth lens 8 and the ninth lens 9 are all glass spherical lenses; the image side surface of the eighth lens 8 and the object side surface of the ninth lens 9 are cemented with each other.

Detailed optical data of this embodiment are shown in table 1.

Table 1 detailed optical data of example one

In this embodiment, the detailed data of the aspheric surfaces of the second lens element 2 and the tenth lens element 10 refer to the following table:

number of noodles

K

A4

A6

A8

A10

A12

A14

L2 S1

0.00

1.231E-05

-3.749E-07

2.307E-09

-1.611E-11

6.690E-14

-1.110E-16

L2 S2

-0.36

-2.001E-05

-9.519E-07

4.315E-09

-7.414E-11

5.197E-13

-1.669E-15

L10 S1

4.42

-1.655E-05

-2.056E-08

3.278E-11

-1.350E-12

6.352E-15

-1.180E-17

L10 S2

-0.83

1.018E-05

-3.990E-08

2.978E-10

-1.662E-12

4.243E-15

-2.497E-19

In this embodiment, the light passing FNO of the lens is 1.7, the actual maximum compatible target surface size is Φ 16mm, and the lens is matched with a 0.47 ″ DMD chip, and is designed by using 100% offset, so that the lens has strong compatible use characteristics.

Fig. 1 is a schematic diagram of an optical path of an optical imaging lens in this embodiment. Please refer to fig. 2, which shows that when the spatial frequency of the lens reaches 93lp/mm, the full-field transfer function image is still larger than 35%, so that the projected image is clear and uniform, and the common problems of the projection lens, such as smear and uneven image quality, do not occur. Referring to fig. 3, the defocus graph of the lens under 460nm-620nm visible light shows that the defocus amount of the lens under visible light is small. Please refer to fig. 4, which shows that the latercolor is less than 5um in the visible 460nm-620nm wide spectrum band, which ensures that the blue edge or red edge of the projection image does not occur, and has high image color reducibility. Please refer to fig. 5 for the field curvature and distortion diagram of the lens under the visible light of 460nm to 620nm, it can be seen from the diagram that the optical distortion is controlled within ± 0.5%, the overall projection frame is uniform, the imaging frame has no obvious deformation, and the image restoration is more accurate. Referring to fig. 6, it can be seen that the relative illumination of the lens under the visible light of 620nm is greater than 75% at the imaging edge of phi 16mm, the overall optical engine has uniform frame brightness, and the F/1.7 large-pass light design is adopted, so that an excessive illumination brightness value is not needed, and damage to the lens or the optical engine structure due to an excessive brightness value is avoided.

Example two

As shown in fig. 7 to 12, the surface convexo-concave shape and the refractive index of each lens of the present embodiment are substantially the same as those of the first embodiment, and the optical parameters such as the curvature radius of the surface of each lens and the thickness of the lens are different.

The detailed optical data of this embodiment are shown in table 2.

Table 2 detailed optical data of example two

Surface of		Caliber size (diameter)	Radius of curvature	Thickness of	Material of	Refractive index	Coefficient of dispersion	Focal length
									0	Shot object surface		Infinity	2000
1	First lens	34.59	35.18	5.57	H-ZBAF21	1.723	38.02	-39.8
									2		25.01	14.82	4.59
3	Second lens	24.80	22.25	3.00	ZEONEX_T62R	1.536	55.98	-44.6
									4		22.64	11.01	8.85
5	Third lens	22.81	-131.22	12.58	H-ZLAF68N	1.883	39.23	45.6
									6		24.00	-32.33	1.93
7	Fourth lens	22.85	-45.76	3.50	H-K9L	1.517	64.21	-88.3
									8		22.39	Infinity	1.60
9	Fifth lens element	24.00	92.25	9.52	H-ZLAF75A	1.904	31.32	39.2
									10		24.00	-55.12	7.53
11	Diaphragm surface	14.39	Infinity	0.10
									12	Sixth lens element	24.00	144.34	3.48	H-ZBAF21	1.723	38.02	-41.4
13		17.00	24.64	3.60
									14	Seventh lens element	15.97	Infinity	6.77	H-ZF52	1.847	23.79	-51.2
15		18.28	43.70	0.31
									16	Eighth lens element	24.00	24.11	10.84	H-ZPK7	1.569	71.31	19.0
17	Ninth lens	24.00	-16.53	2.74	H-ZLAF56B	1.806	33.29	-48.3
									18		23.00	-30.71	0.29
19	Tenth lens	24.11	45.06	13.28	M-PCD51	1.592	67.02	31.6
									20		24.73	-28.58	4.00
21	Image rotating prism	22.45	Infinity	15.50	H-LAK7A	1.713	53.87	Infinity
									22		19.31	Infinity	6.00
23	Cover glass	17.20	Infinity	3.10	H-K9L	1.517	64.21	Infinity
									24		16.49	Infinity	1.35
25	Image plane	16.02	Infinity

In this embodiment, the detailed data of the aspheric surfaces of the second lens element 2 and the tenth lens element 10 refer to the following table:

in this embodiment, the light passing FNO of the lens is 1.7, the actual maximum compatible target surface size is Φ 16mm, and the lens is matched with a 0.47 ″ DMD chip, and is designed by using 100% offset, so that the lens has strong compatible use characteristics.

Fig. 7 is a schematic diagram of an optical path of an optical imaging lens in this embodiment. Please refer to fig. 8, which shows that when the spatial frequency of the lens reaches 93lp/mm, the full-field transfer function image is still greater than 30%, so that the projected image is clear and uniform, and the common problems of the projection lens, such as smear and uneven image quality, do not occur. Referring to fig. 9, the defocus graph of the lens under 460nm-620nm visible light shows that the defocus amount of the lens under visible light is small. Please refer to fig. 10, which shows that the latercolor is less than 5um in the visible 460nm-620nm wide spectrum band, which ensures that the blue edge or red edge of the projected image does not occur, and has high image color reducibility. Please refer to fig. 11 for the field curvature and distortion diagram of the lens under the visible light of 460nm to 620nm, it can be seen from the diagram that the optical distortion is controlled within ± 0.5%, the overall projection frame is uniform, the imaging frame has no obvious deformation, and the image restoration is more accurate. Referring to fig. 12, it can be seen that the relative illumination of the lens under the visible light of 620nm is greater than 65% at the imaging edge Φ 16mm, the overall optical engine has uniform frame brightness, and the F/1.7 large-pass light design is adopted, so that an excessive illumination brightness value is not needed, and damage to the lens or the optical engine structure due to an excessive brightness value is avoided.

EXAMPLE III

As shown in fig. 13 to 18, the surface convexoconcave and the refractive index of each lens of the present embodiment are substantially the same as those of the first embodiment, and the optical parameters such as the curvature radius of the surface of each lens and the thickness of the lens are different.

The detailed optical data of this embodiment are shown in table 3.

Table 3 detailed optical data of example three

In this embodiment, the detailed data of the aspheric surfaces of the second lens element 2 and the tenth lens element 10 refer to the following table:

number of noodles

K

A4

A6

A8

A10

A12

A14

L2 S1

0.00

2.128E-06

-4.076E-07

2.294E-09

-1.577E-11

6.690E-14

-1.089E-16

L2 S2

-0.35

-3.105E-05

-9.512E-07

4.603E-09

-7.269E-11

5.300E-13

-1.590E-15

L10 S1

3.57

-1.772E-05

-3.581E-08

2.038E-11

-1.319E-12

4.178E-15

-2.424E-17

L10 S2

-0.16

5.757E-06

-4.486E-08

2.291E-10

-2.008E-12

5.025E-15

-1.537E-17

In this embodiment, the light passing FNO of the lens is 1.7, the actual maximum compatible target surface size is Φ 16mm, and the lens is matched with a 0.47 ″ DMD chip, and is designed by using 100% offset, so that the lens has strong compatible use characteristics.

Fig. 13 is a schematic diagram of an optical path of an optical imaging lens in this embodiment. Please refer to fig. 14, which shows the MTF curve of the lens under the visible light of 460nm to 620nm, when the spatial frequency of the lens reaches 93lp/mm, the full-field transfer function image is still larger than 30%, so that the projected image is clear and uniform, and the problems of the projection lens, such as smear, uneven image quality of the image, and the like, are avoided. Referring to fig. 15, the defocus graph of the lens under 460nm-620nm visible light shows that the defocus amount of the lens under visible light is small. Please refer to fig. 16, which shows that the latercolor is less than 5um in the visible 460nm-620nm wide spectrum band, which ensures that the blue edge or red edge of the projected image does not occur, and has high image color reducibility. Please refer to fig. 17 for the field curvature and distortion diagram of the lens under the visible light of 460nm to 620nm, it can be seen from the diagram that the optical distortion is controlled within ± 0.5%, the overall projection frame is uniform, the imaging frame has no obvious deformation, and the image restoration is more accurate. Referring to fig. 18, it can be seen that the relative illumination of the lens under the visible light of 620nm is greater than 65% at the imaging edge Φ 16mm, the overall optical engine has uniform frame brightness, and the F/1.7 large-pass light design is adopted, so that an excessive illumination brightness value is not needed, and damage to the lens or the optical engine structure due to an excessive brightness value is avoided.

Example four

As shown in fig. 19 to 24, the surface convexoconcave and the refractive index of each lens of the present embodiment are substantially the same as those of the first embodiment, and the optical parameters such as the curvature radius of the surface of each lens and the thickness of the lens are different.

The detailed optical data of this embodiment are shown in table 4.

Table 4 detailed optical data for example four

In this embodiment, the detailed data of the aspheric surfaces of the second lens element 2 and the tenth lens element 10 refer to the following table:

number of noodles

K

A4

A6

A8

A10

A12

A14

L2 S1

0.00

1.249E-06

-4.070E-07

2.294E-09

-1.573E-11

6.739E-14

-1.134E-16

L2 S2

-0.35

-3.042E-05

-9.496E-07

4.598E-09

-7.294E-11

5.279E-13

-1.587E-15

L10 S1

3.41

-1.807E-05

-3.656E-08

2.185E-11

-1.287E-12

4.402E-15

-1.894E-17

L10 S2

-0.24

6.314E-06

-4.431E-08

2.305E-10

-1.970E-12

5.501E-15

-1.300E-17

In this embodiment, the light passing FNO of the lens is 1.7, the actual maximum compatible target surface size is Φ 16mm, and the lens is matched with a 0.47 ″ DMD chip, and is designed by using 100% offset, so that the lens has strong compatible use characteristics.

Fig. 19 is a schematic diagram of an optical path of an optical imaging lens in this embodiment. Please refer to fig. 20, which shows that when the spatial frequency of the lens reaches 93lp/mm, the full-field transfer function image is still larger than 35%, so that the projected image is clear and uniform, and the common problems of the projection lens, such as smear and uneven image quality, do not occur. Please refer to fig. 21, which shows the defocus curve of the lens in the visible light of 460nm-620nm, and it can be seen that the defocus of the lens in the visible light is small. Please refer to fig. 22, which shows that the latercolor is less than 5um in the visible 460nm-620nm wide spectrum band, which ensures that the blue edge or red edge of the projected image does not occur, and has high image color reducibility. Please refer to fig. 23 for the field curvature and distortion diagram of the lens under the visible light of 460nm to 620nm, it can be seen from the diagram that the optical distortion is controlled within ± 0.5%, the overall projection frame is uniform, the imaging frame has no obvious deformation, and the image restoration is more accurate. Referring to fig. 24, it can be seen that the relative illumination of the lens under the visible light of 620nm is greater than 65% at the imaging edge Φ 16mm, the overall optical engine has uniform frame brightness, and the F/1.7 large-pass light design is adopted, so that an excessive illumination brightness value is not needed, and damage to the lens or the optical engine structure due to an excessive brightness value is avoided.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (8)

1. The large-light-passing high-illumination projection lens matched with the 0.47DMD is characterized by sequentially comprising a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a diaphragm, a sixth lens, a seventh lens, an eighth lens, a ninth lens and a tenth lens from an object side to an image side along an optical axis, wherein the first lens to the tenth lens respectively comprise an object side surface facing the object side and allowing imaging light to pass and an image side surface facing the image side and allowing the imaging light to pass;

the first lens element with negative refractive index has a convex object-side surface and a concave image-side surface;

the second lens element with negative refractive index has a convex object-side surface and a concave image-side surface;

the third lens element with positive refractive index has a concave object-side surface and a convex image-side surface;

the fourth lens element has a negative refractive index, and has a concave object-side surface and a planar image-side surface;

the fifth lens element with positive refractive index has a convex object-side surface and a convex image-side surface;

the sixth lens element with negative refractive index has a convex object-side surface and a concave image-side surface;

the seventh lens element with negative refractive index has a concave object-side surface or a plane surface and a concave image-side surface;

the eighth lens element with a positive refractive index has a convex object-side surface and a convex image-side surface;

the ninth lens element with negative refractive index has a concave object-side surface and a convex image-side surface;

the tenth lens element with a positive refractive index has a convex object-side surface and a convex image-side surface;

the optical imaging lens has only ten lenses with refractive indexes.

2. The lens assembly of claim 1, wherein the second lens element is a plastic high-order even aspheric lens element.

3. The lens assembly of claim 1, wherein the tenth lens element is a high-order aspheric glass lens.

4. The projection lens with large light transmittance and high illumination degree matched with 0.47DMD of claim 1, wherein the first lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens and the ninth lens are all glass spherical lenses, wherein the eighth lens is made of a material with a negative temperature coefficient of refractive index dn/dt.

5. The projection lens with large light transmittance and high illumination intensity matched with 0.47DMD of claim 4, wherein the following conditional expressions are satisfied:

-4.0＜(f1/f)＜-3.0，3.0＜(f3/f)＜-4.0，-7.5＜(f4/f)＜-5.5，

2.5＜(f5/f)＜3.5，-4.5＜(f6/f)＜-3.0，-5.5＜(f7/f)＜-3.5，

1.5＜(f8/f)＜2.5，-5＜(f9/f)＜-3.0，

wherein f is a focal length value of the lens, and f1, f3, f4, f5, f6, f7, f8 and f9 are focal length values of the first lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens and the ninth lens, respectively.

6. The projection lens with large light transmittance and high illumination intensity matched with a 0.47DMD of claim 1, wherein an image side surface of the eighth lens element and an object side surface of the ninth lens element are mutually glued, and the following conditional expressions are satisfied: vd8 is more than 70, Vd9 is less than 35, wherein, Vd8 is the abbe number of the eighth lens, and Vd9 is the abbe number of the ninth lens.

7. The lens of claim 1, wherein the first lens element has an effective aperture D1, D1 < phi 36.00 mm.

8. The projection lens with large light transmittance and high illumination intensity matched with 0.47DMD of claim 1, wherein the following conditional expressions are satisfied:

10.2＜TTL/f＜10.6,3.0＜BFL/f＜3.6,

wherein, TTL is the distance on the optical axis from the object-side surface of the first lens element to the imaging surface, BFL is the distance from the tenth lens element of the lens element to the DMD surface, and f is the focal length of the lens element.

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