CN102231039B - Projection device - Google Patents
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- CN102231039B CN102231039B CN 201110179252 CN201110179252A CN102231039B CN 102231039 B CN102231039 B CN 102231039B CN 201110179252 CN201110179252 CN 201110179252 CN 201110179252 A CN201110179252 A CN 201110179252A CN 102231039 B CN102231039 B CN 102231039B
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Abstract
The invention provides a projection device which comprises an image generation device and a projection lens. The projection lens is arranged between a light valve of the image generation device and a projection screen, and the projection lens comprises a plurality of lenses. The lenses comprise a first lens, a second lens and a third lens which are aspherical lenses. The effective focal length of the projection lens is between 5mm and 8mm, and the sum of the effective focal length millimeter value of the projection lens and the lens number is between 14 and 17. According to the invention, the projection device can achieve the effects of short focal length and large projection angle, thus the lens number of the projection device can be effectively reduced and the problem of overweight projection device can be further solved.
Description
Technical field
The present invention is about a kind of projection arrangement, espespecially a kind of projection arrangement with projection lens of at least three aspherical lens.
Background technology
Along with science and technology is maked rapid progress, projection arrangement is being played the part of indispensable role gradually on family, amusement or business practice.The tradition projection arrangement is comprised of image generation device and projection lens, and image generation device produces image by the projection lens amplification and is projected on the projection screen.
Because the eyeglass of making projection lens is to adopt the sphere design in the past, so need to use many eyeglasses to solve the problems such as aberration and image fog be out of focus in the projection lens, and cause the size of projection lens and weight to be restricted.Please refer to Fig. 1, Fig. 1 is the synoptic diagram of known projection lens.As shown in Figure 1, known projection lens 10 need use 14 eyeglasses 12 for use (diagonal line) size of arranging in pairs or groups greater than the image generation device more than 0.4 inch, eliminate aberration and image distortion, and the minute surface of each eyeglass 12 is spherical mirror surface.Therefore, in the situation that shortens gradually focal length, the eyeglass 12 of projection lens 10 increases in numbers swiftly.Yet, along with projection arrangement towards compact trend development, the eyeglass quantity of projection lens too much can cause the volume of projection arrangement to be restricted and can't dwindle, and easily because of the preponderance of projection arrangement, and causes user's burden.
Therefore, provide the projection arrangement that has simultaneously large projection visual angle, small size and lightweight characteristic real target of making great efforts for industry.
Summary of the invention
Fundamental purpose of the present invention is to provide a kind of projection arrangement, to improve the problem that causes the projection arrangement preponderance because shortening focal length.
For reaching above-mentioned purpose, the invention provides a kind of projection arrangement, be used for image projection to projection screen.Projection arrangement comprises image generation device and projection lens.Image generation device has the projection light of image in order to generation, and image generation device has light valve, and projection light is penetrated from light valve.Projection lens is located between light valve and the projection screen, and projection lens comprises a plurality of eyeglasses.Eyeglass has optical axis, and projection light produces projection image through eyeglass on projection screen, and wherein eyeglass comprises the first eyeglass, the second eyeglass and prismatic glasses, and the first eyeglass, the second eyeglass and prismatic glasses are aspherical lens.Eyeglass satisfies the first relational expression 14≤(EFL+N)≤17 and the second relational expression 5≤EFL≤8, and wherein EFL is the effective focal length millimeter value of projection lens, and N is the quantity of eyeglass.
According to projection arrangement of the present invention, the center of projection image and the center of light valve be a both sides at optical axis respectively.
According to projection arrangement of the present invention, in these a plurality of eyeglasses, the first eyeglass is the eyeglass of contiguous projection screen.
According to projection arrangement of the present invention, in these a plurality of eyeglasses, the second eyeglass is the eyeglass of contiguous light valve.
Also comprise the light hurdle according to projection arrangement of the present invention, be arranged between the first eyeglass and the second eyeglass.Further, prismatic glasses is located between this light hurdle and this second eyeglass.
According to projection arrangement of the present invention, the first eyeglass, the second eyeglass and prismatic glasses have respectively two aspherical mirrors.
According to projection arrangement of the present invention, the catercorner length of light valve is greater than 0.4 inch (inch).
Projection arrangement of the present invention uses at least three aspherical lens, make its effective focal length between 5mm and 8mm, to have the effect at short focal length and large projection visual angle, and the summation of the eyeglass quantity of the effective focal length of projection arrangement of the present invention and projection arrangement is between 14 and 17, eyeglass quantity is defined between 6 to 12, more can effectively reduce the eyeglass quantity of projection arrangement, and then solve the overweight problem of projection arrangement.
Description of drawings
Fig. 1 is the synoptic diagram of known projection lens.
Fig. 2 is the synoptic diagram of projection arrangement of the present invention.
Fig. 3 is the synoptic diagram of the projection lens of the present invention's one first preferred embodiment.
Fig. 4 is the synoptic diagram of the projection arrangement of the present invention's one second preferred embodiment.
Embodiment
For making purpose of the present invention, structure, feature and function thereof there are further understanding, hereby cooperate embodiment to be described in detail as follows.
Please refer to Fig. 2, Fig. 2 is the synoptic diagram of projection arrangement of the present invention.As shown in Figure 2, projection arrangement 100 is used for image 102 is projected to projection screen 104, and projection arrangement 100 comprises image generation device 106 and projection lens 108.Wherein, image generation device 106 is for generation of the projection light with image 102.Image generation device 106 has light valve 110, and projection light is penetrated from light valve 110.The image generation device 106 of present embodiment can be the optical-mechanical system (light engine) that comprises light source, various optical element etc., and light valve can for example be liquid crystal panel (LCD panel), numerical digit micro-mirror element (digital micro-mirror device, DMD), but image generation device of the present invention and light valve not as limit.Projection lens 108 is arranged between projection screen 104 and the light valve 110, and comprise a plurality of eyeglasses, and having optical axis 112, the projection light that penetrates from light valve 110 by this can be projected on the projection screen 104 by projection lens 108, to present the projection image 114 of amplification on projection screen 104.And, projection lens 108 has effective focal length, satisfy the first relational expression 14≤(EFL+N)≤17 and the second relational expression 5≤EFL≤8, wherein EFL is the effective focal length millimeter value (being the numerical value before the mm of unit) of projection lens, and N is the quantity of eyeglass.In other words, the quantity of eyeglass is between 6 to 12.Hence one can see that, projection arrangement of the present invention 100 adopt Polaroid mode with image 102 imagings of standing upside down to projection screen 104, and form projection image 114 upright and that amplify.And the center of the center of projection image 114 and light valve 110 is a both sides at optical axis 112 respectively.In addition, the catercorner length of light valve is slightly larger than 0.4 inch (inch) approximately.
In order to clearly demonstrate projection lens of the present invention, please refer to Fig. 3, and in the lump with reference to figure 2.Fig. 3 is the synoptic diagram of the projection lens of the present invention's one first preferred embodiment.As shown in Figure 3, the eyeglass of present embodiment can be divided into the first eyeglass L11, the second eyeglass L12, prismatic glasses L13, the 4th eyeglass L14, the 5th eyeglass L15, the 6th eyeglass L16, the 7th eyeglass L17 and the 8th eyeglass L18, wherein the first eyeglass L11, the second eyeglass L12 and prismatic glasses L13 are aspherical lens, and the 4th eyeglass L14, the 5th eyeglass L15, the 6th eyeglass L16, the 7th eyeglass L17 and the 8th eyeglass L18 are spheric glass.These lens are sequentially the first eyeglass L11, the 4th eyeglass L14, the 5th eyeglass L15, the 6th eyeglass L16, prismatic glasses L13, the 7th eyeglass L17, the 8th eyeglass L18 and the second eyeglass L12 from the order of a side of the extremely contiguous light valve 110 of a side of contiguous projection screen 104, that is first eyeglass L11 be the most contiguous projection screen in these eyeglasses, and the second eyeglass L12 is the most contiguous light valve in these eyeglasses.In addition, projection lens 108 comprises light hurdle 116 in addition, be located between the 6th eyeglass L16 and the prismatic glasses L13, and the spacing of light hurdle 116 and the 6th eyeglass L16 is greater than the spacing of light hurdle 116 and prismatic glasses L13.Wherein, prismatic glasses L13 is the one on adjacent light hurdle 116 in the aspherical lens.In present embodiment, the first eyeglass L11 is meniscus, and has convex lens face S11 and the concave mirror surface S12 that faces light valve 110 in the face of projection screen 104.The second eyeglass L12 is biconvex lens, and has in the face of the convex lens face S13 of projection screen 104 and the convex lens face S14 that faces light valve 110.Prismatic glasses L13 is concave-convex lens, and has in the face of the concave mirror surface S15 of projection screen 104 and the convex lens face S16 that faces light valve 110.The 4th eyeglass L14 is biconcave lens, and has in the face of the concave mirror surface S17 of projection screen 104 and the concave mirror surface S18 that faces light valve 110.The 5th eyeglass L15 is biconvex lens, and has in the face of the convex lens face S19 of projection screen 104 and the convex lens face S110 that faces light valve 110.The 6th eyeglass L16 is meniscus, and has in the face of the convex lens face S111 of projection screen 104 and the concave mirror surface S112 that faces light valve 110.The 7th eyeglass L17 is biconvex lens, and has in the face of the convex lens face S113 of projection screen 104 and the convex lens face S114 that faces light valve 110.The 8th eyeglass L18 is biconcave lens, and have in the face of the concave mirror surface S115 of projection screen 104 and the concave mirror surface S116 that faces light valve 110, wherein the concave mirror surface S115 of the 8th eyeglass L18 overlaps in the face of the convex lens face S114 of light valve 110 with the 7th eyeglass L17, and has identical radius-of-curvature.And the first eyeglass L11 to the eight eyeglass L18 of present embodiment are made of plastic cement, and the optical data of its minute surface and configuration relation be recited in the table 1, but the present invention is not as limit.In table 1, the value of " thickness " represents the distance on surface to the surface of next column of corresponding these row, the i.e. spacing of the minute surface of the minute surface of these row and next column.
Table 1
And two convex lens face S13, the S14 of the convex lens face S11 of the first eyeglass L11 and concave mirror surface S12, the second eyeglass L12 and concave mirror surface S15 and the convex lens face S16 of prismatic glasses L13 are all aspherical mirror, and the surperficial polynomial expression of aspherical mirror can be expressed as:
Wherein z is the depression degree (sag) of aspherical mirror, r is the aperture radius of aspherical mirror, a is the radius-of-curvature at aspheric mirror vertex of surface place, and b is the circular cone coefficient, and c, d, e, f are the asphericity coefficient that is respectively quadravalence, six rank, eight rank and ten rank.The asphericity coefficient of two convex lens face S13, the S14 of the convex lens face S11 of the first eyeglass L11 of present embodiment and concave mirror surface S12, the second eyeglass L12 and the concave mirror surface S15 of prismatic glasses L13 and convex lens face S16 is recited in (numerical value represents with the form of science counting) in the table 2, but the present invention is not as limit.
Table 2
| Minute surface | b | c | d | e | f |
| S11 | -1.519E+01 | 2.550E-06 | 3.278E-09 | -4.164E-12 | 3.192E-15 |
| S12 | -6.668E-01 | -1.538E-05 | -5.110E-08 | 2.063E-10 | -3.928E-13 |
| S15 | -8.798E+01 | 2.234E-04 | 1.245E-06 | -9.167E-08 | 5.578E-11 |
| S16 | 0.000E+00 | 4.196E-04 | -8.062E-06 | 1.429E-07 | -5.416E-09 |
| S13 | -1.934E+00 | -1.989E-04 | 2.798E-06 | -3.245E-08 | 1.991E-10 |
| S14 | -6.003E-01 | -2.790E-05 | -3.526E-07 | -7.187E-10 | 1.474E-11 |
By above-mentioned data as can be known, the effective focal length of the projection lens 108 of present embodiment is 6.95mm (EFL is 6.95) approximately slightly, and about slightly 60 degree in the projection visual angle of projection lens 108.And, the projection lens 108 of present embodiment only uses three aspherical lens can have the effect of effective focal length between 5mm and 8mm, and the total quantity of the eyeglass of projection lens 108 only is eight, therefore not only has the effect of short focal length, more can reduce the eyeglass quantity of projection lens 108, to reduce the overall weight of projection lens 108.
In addition, projection lens of the present invention is not limited with above-described embodiment.Please refer to Fig. 4, Fig. 4 is the synoptic diagram of the projection arrangement of the present invention's one second preferred embodiment.As shown in Figure 4, the eyeglass of the projection lens 200 of present embodiment can be divided into the first eyeglass L21, the second eyeglass L22, prismatic glasses L23, the 4th eyeglass L24, the 5th eyeglass L25, the 6th eyeglass L26, the 7th eyeglass L27, the 8th eyeglass L28, the 9th eyeglass L29, the tenth eyeglass L210 and the 11 eyeglass L211, the first eyeglass L21 wherein, the second eyeglass L22 and prismatic glasses L23 are aspherical lens, and the 4th eyeglass L24, the 5th eyeglass L25, the 6th eyeglass L26, the 7th eyeglass L27, the 8th eyeglass L28, the 9th eyeglass L29, the tenth eyeglass L210 and the 11 eyeglass L211 are spheric glass.The eyeglass of present embodiment is sequentially the first eyeglass L21, the 4th eyeglass L24, the 5th eyeglass L25, the 6th eyeglass L26, the 7th eyeglass L27, the 8th eyeglass L28, prismatic glasses L23, the 9th eyeglass L29, the tenth eyeglass L210, the 11 eyeglass L211 and the second eyeglass L22 from the order of a side of the extremely contiguous light valve 110 of a side of contiguous projection screen 104.The first eyeglass L21 is the most contiguous projection screen in these eyeglasses, and the second eyeglass L22 is the most contiguous light valve in these eyeglasses.In addition, the light hurdle 116 of projection lens 200 is located between the 7th eyeglass L27 and the 8th eyeglass L28, and the spacing of light hurdle 116 and the 7th eyeglass L27 is greater than the spacing of light hurdle 116 and the 8th eyeglass L28.Wherein, prismatic glasses L23 is adjacent light hurdle in the aspherical lens.In addition, the first eyeglass L21 of present embodiment is meniscus, and has convex lens face S21 and the concave mirror surface S22 that faces light valve 110 in the face of projection screen 104.The second eyeglass L22 is biconvex lens, and has in the face of the convex lens face S23 of projection screen 104 and the convex lens face S24 that faces light valve 110.Prismatic glasses L23 is biconvex lens, and has in the face of the convex lens face S25 of projection screen 104 and the convex lens face S26 that faces light valve 110.The 4th eyeglass L24 is meniscus, and has in the face of the convex lens face S27 of projection screen 104 and the concave mirror surface S28 that faces light valve 110.The 5th eyeglass L25 is biconcave lens, and has in the face of the concave mirror surface S29 of projection screen 104 and the concave mirror surface S210 that faces light valve 110.The 6th eyeglass L26 is biconvex lens, and has in the face of the convex lens face S211 of projection screen 104 and the convex lens face S212 that faces light valve 110.The 7th eyeglass L27 is meniscus, and has in the face of the convex lens face S213 of projection screen 104 and the concave mirror surface S214 that faces light valve 110.The 8th eyeglass L28 is biconcave lens, and has in the face of the concave mirror surface S215 of projection screen 104 and the concave mirror surface S216 that faces light valve 110.The 9th eyeglass L29 is biconcave lens, and has in the face of the concave mirror surface S217 of projection screen 104 and the concave mirror surface S218 that faces light valve 110.The tenth eyeglass L210 is biconvex lens, and has in the face of the convex lens face S219 of projection screen 104 and the convex lens face S220 that faces light valve 110.The 11 eyeglass L211 is recessed plano lens, and have in the face of the concave mirror surface S221 of projection screen 104 and the flat mirror S222 that faces light valve 110, wherein the concave mirror surface S221 of the 11 eyeglass L211 overlaps in the face of the convex lens face S220 of light valve 110 with the tenth eyeglass L210, and has identical radius-of-curvature.And optical data and the configuration relation of the minute surface of the first eyeglass L21 to the 11 eyeglass L211 of present embodiment are recited in the table 3, but the present invention is not as limit.In table 3, the value of " thickness " represents the distance on surface to the surface of next column of corresponding these row, the i.e. spacing of the minute surface of the minute surface of these row and next column.
Table 3
And, two convex lens face S23, the S24 of the convex lens face S21 of the first eyeglass L21 of present embodiment and concave mirror surface S22, the second eyeglass L22 and two convex lens face S25, the S26 of prismatic glasses L23 also are aspherical mirror, and according to above-mentioned surperficial polynomial expression, the asphericity coefficient of two convex lens face S23, the S24 of the convex lens face S21 of the first eyeglass L21 of present embodiment and concave mirror surface S22, the second eyeglass L22 and two convex lens face S25, the S26 of prismatic glasses L23 can be recited in (numerical value represents with the form of science counting) in the table 4, but the present invention is not as limit.
Table 4
| Minute surface | b | c | d | e | f |
| S21 | -7.815E+00 | 3.769E-06 | 1.413E-10 | -4.141E-13 | 3.216E-16 |
| S22 | -6.864E-01 | -5.104E-06 | -4.883E-08 | 1.796E-10 | -3.010E-13 |
| S25 | 1.572E+00 | -3.222E-04 | -1.552E-05 | 6.183E-07 | -2.979E-08 |
| S26 | -3.930E+00 | -2.783E-05 | 1.016E-05 | -5.557E-07 | 1.953E-08 |
| S23 | 5.089E+00 | 1.817E-04 | 3.564E-07 | 1.489E-09 | 9.106E-11 |
| S24 | -1.698E+00 | 1.657E-04 | 3.993E-06 | 4.985E-08 | 1.974E-10 |
According to above-mentioned data, the effective focal length of the projection lens 200 of present embodiment system is 5.22mm (EFL is 5.22) approximately slightly, and about slightly 67.2 degree in the projection visual angle of projection lens 200.And, the projection lens 200 of present embodiment only uses three aspherical lens can have the effect of effective focal length between 5mm and 8mm, and the total quantity of the eyeglass of projection lens 200 only is ten a slices, therefore not only can by shortening focal length to promote the projection visual angle of projection lens 200, more can avoid excessively increasing the overall weight of projection lens 200.
In sum, projection arrangement of the present invention uses at least three aspherical lens, make its effective focal length between 5mm and 8mm, to have the effect at short focal length and large projection visual angle, and the summation of the eyeglass quantity of the effective focal length of projection arrangement of the present invention and projection arrangement is between 14 and 17, eyeglass quantity is defined between 6 to 12, more can effectively reduces the eyeglass quantity of projection arrangement.
The present invention is described by above-mentioned related embodiment, yet above-described embodiment is only for implementing example of the present invention.Must be pointed out that the embodiment that has disclosed does not limit the scope of the invention.On the contrary, the change of doing without departing from the spirit and scope of the present invention and retouching all belong to scope of patent protection of the present invention.
Claims (7)
1. projection arrangement is used for image projection to projection screen, and this projection arrangement comprises:
Image generation device has the projection light of this image in order to generation, and this image generation device has light valve, and this projection light is penetrated from this light valve; And
Projection lens is located between this light valve and this projection screen, and is had optical axis, it is characterized in that this projection lens comprises:
A plurality of eyeglasses, this projection light produces projection image through these a plurality of eyeglasses on this projection screen, wherein these a plurality of eyeglasses comprise the first eyeglass, the second eyeglass and prismatic glasses, and this first eyeglass, this second eyeglass and this prismatic glasses are aspherical lens, in these a plurality of eyeglasses, this first eyeglass is the eyeglass of contiguous this projection screen;
Wherein these a plurality of eyeglasses satisfy the first relational expression 14＜=(EFL+N)＜=17 and the second relational expression 5＜=EFL＜=8, and wherein EFL is the effective focal length millimeter value of this projection lens, and N is the quantity of these a plurality of eyeglasses.
2. projection arrangement as claimed in claim 1 is characterized in that the center of this projection image and a center difference both sides at this optical axis of this light valve.
3. projection arrangement as claimed in claim 1 is characterized in that in these a plurality of eyeglasses, and this second eyeglass is the eyeglass of contiguous this light valve.
4. projection arrangement as claimed in claim 1 characterized by further comprising the light hurdle, is arranged between this first eyeglass and this second eyeglass.
5. projection arrangement as claimed in claim 4 is characterized in that this prismatic glasses is located between this light hurdle and this second eyeglass.
6. projection arrangement as claimed in claim 1 is characterized in that this first eyeglass, this second eyeglass and this prismatic glasses have respectively two aspherical mirrors.
7. projection arrangement as claimed in claim 1 is characterized in that the catercorner length of this light valve is greater than 0.4 inch.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110179252 CN102231039B (en) | 2011-06-29 | 2011-06-29 | Projection device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110179252 CN102231039B (en) | 2011-06-29 | 2011-06-29 | Projection device |
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| Publication Number | Publication Date |
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| CN102231039A CN102231039A (en) | 2011-11-02 |
| CN102231039B true CN102231039B (en) | 2013-03-06 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201110179252 Active CN102231039B (en) | 2011-06-29 | 2011-06-29 | Projection device |
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Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103869450B (en) * | 2012-12-18 | 2016-07-13 | 广景科技有限公司 | LED digital micro projection lens of projector |
| CN108241202B (en) * | 2016-12-23 | 2020-01-17 | 信泰光学(深圳)有限公司 | Imaging lens |
| CN114967066B (en) * | 2022-07-26 | 2022-11-29 | 江西晶超光学有限公司 | Optical system, image capturing module and electronic equipment |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5870228A (en) * | 1996-05-24 | 1999-02-09 | U.S. Precision Lens Inc. | Projection lenses having larger back focal length to focal length ratios |
| US6853493B2 (en) * | 2003-01-07 | 2005-02-08 | 3M Innovative Properties Company | Folded, telecentric projection lenses for use with pixelized panels |
| CN101373259B (en) * | 2007-08-24 | 2010-06-23 | 鸿富锦精密工业（深圳）有限公司 | Projector lens |
| CN101995645B (en) * | 2009-08-26 | 2012-09-26 | 亚洲光学股份有限公司 | Zoom lens |
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