CN101210998B - an optical lens - Google Patents

Abstract

Translated fromChinese

本发明公开了一种光学镜头，包括同轴排列的第一、二和三镜片，所述第一镜片的表面为球面，第二、三镜片的表面为非球面，所述第二、三镜片的表面形状满足如下函数：

该光学镜头满足如下关系式：1.25＜f/L＜1.4；0.5＜f1/f＜0.8；f2＜0且0.65＜|f2/f|＜1；1.3＜f3/f＜1.6；其中，f为光学镜头的有效焦距值；f1为第一镜片的有效焦距值；f2为第二镜片的有效焦距值；f3为第三镜片的有效焦距值；L为空气换算距离后的光学镜头总长。本发明的光学镜头成像质量好、总长短、亮度高视场角大、出射角小、最低相对照度在50％以上、小巧轻薄、光学性能好。

The invention discloses an optical lens, comprising first, second and third mirrors arranged coaxially, the surface of the first mirror is spherical, the surfaces of the second and third mirrors are aspherical, the second and third mirrors are The surface shape of satisfies the following function:

The optical lens satisfies the following relationship: 1.25<f/L<1.4;0.5<f1/f<0.8;f2<0 and 0.65<|f2/f|<1;1.3<f3/f<1.6; where f is The effective focal length value of the optical lens; f1 is the effective focal length value of the first lens; f2 is the effective focal length value of the second lens; f3 is the effective focal length value of the third lens; L is the total length of the optical lens after air conversion distance. The optical lens of the invention has the advantages of good imaging quality, short overall length, high brightness, large viewing angle, small exit angle, minimum relative illuminance above 50%, compactness, lightness, and good optical performance.

Description

Translated fromChinese

一种光学镜头an optical lens

技术领域technical field

本发明涉及光学器件，尤其涉及一种光学镜头。The invention relates to optical devices, in particular to an optical lens.

背景技术Background technique

光学镜头是数码成像设备的重要组件，镜头的成像质量直接决定了数码成像设备的成像性能。近年来，数码产品不断更新换代，日趋向轻薄短小方向发展。因而对配备在数码成像设备中的光学镜头有了越来越高的要求，具体表现如下：Optical lens is an important component of digital imaging equipment, and the imaging quality of the lens directly determines the imaging performance of digital imaging equipment. In recent years, digital products have been continuously updated, and they are increasingly developing in the direction of thinner, lighter and smaller. Therefore, there are higher and higher requirements for optical lenses equipped in digital imaging equipment, as follows:

1.优良的成像品质。适配百万象素的镜头分辨率要达到160lp/mmMTF≥0.3；1. Excellent imaging quality. The resolution of the lens suitable for megapixels must reach 160lp/mmMTF≥0.3;

2.小巧，轻薄。即要求总长短，镜片数目少，后焦适当；2. Small and light. That is to say, the total length is required, the number of lenses is small, and the back focus is appropriate;

3.高亮度。即F/#数小，最大出射角≤20°，相对照度≥50％；3. High brightness. That is, the F/# number is small, the maximum exit angle is ≤20°, and the relative illuminance is ≥50%;

4.足够的视场角。为了满足民用拍摄的要求，视场角一般≥60°；4. Sufficient viewing angle. In order to meet the requirements of civilian shooting, the field of view is generally ≥60°;

5.低成本。即在保证成像质量的前提下尽量使用低廉材质替代昂贵材质。采用更易实现的加工工艺5. Low cost. That is, under the premise of ensuring the image quality, try to use cheap materials instead of expensive materials. Adopt easier processing technology

而现有的镜头设计中，为了适配于高象素数码设备，往往采用增加镜片的数量或采用高折射率低色散的优质玻璃材质的方法来校正像差，提高成像质量。从而增加了镜头体积，提高了成本。However, in existing lens designs, in order to adapt to high-pixel digital devices, the method of increasing the number of lenses or using high-quality glass materials with high refractive index and low dispersion is often used to correct aberrations and improve image quality. Thereby increasing the size of the lens and increasing the cost.

如中国专利CN200420043494.3，采用的三片塑料非球面镜片，但焦距在4.8左右，总长达到了8mm。远远达不到现在数码产品轻薄短小的要求。For example, the Chinese patent CN200420043494.3 adopts three plastic aspheric lenses with a focal length of about 4.8 and a total length of 8mm. It is far from meeting the requirements of thin, light and small digital products.

发明内容Contents of the invention

本发明所要解决的一个技术问题是，克服上述现有技术的缺陷，提出一种轻薄短小的光学镜头。A technical problem to be solved by the present invention is to overcome the above-mentioned defects of the prior art and propose a light, thin and small optical lens.

其技术问题通过以下的技术方案予以解决：Its technical problem is solved by following technical scheme:

一种光学镜头，包括同轴排列的第一、二、三镜片，所述第一镜片的表面为球面，所述第二、三镜片的表面为非球面，所述第二、三镜片的表面形状满足如下函数：An optical lens, comprising first, second and third mirrors arranged coaxially, the surface of the first mirror is spherical, the surface of the second and third mirrors is aspheric, the surface of the second and third mirrors The shape satisfies the following function:

$z=\frac{{\mathrm{cr}}^2}{1-\sqrt{1-(1+k)c^2{r}^2}}+a_2{r}^2+a_4{r}^4+a_6{r}^6+a_8{r}^8+a_{10}{r}^{10}+a_{12}{r}^{12},$其中，z为以各非球面与光轴交点为起点且垂直光轴方向的轴向值，k为二次曲面系数，c为镜面中心曲率，r为镜面中心高度；a2、a4、a6、a8、a10、a12为非球面系数；该光学镜头满足如下关系式：$z=\frac{{\mathrm{<figure-callout\; label="cr"\; filenames="H2006101577350E00011.png"\; state="\{\{state\}\}">cr</figure-callout>}}^2}{1-\sqrt{1-(1+k)c^2{\mathrm{<figure-callout\; label="r"\; filenames="H2006101577350E00011.png"\; state="\{\{state\}\}">r</figure-callout>}}^2}}+a_2{\mathrm{<figure-callout\; label="r"\; filenames="H2006101577350E00011.png"\; state="\{\{state\}\}">r</figure-callout>}}^2+a_4{\mathrm{<figure-callout\; label="r"\; filenames="H2006101577350E00011.png"\; state="\{\{state\}\}">r</figure-callout>}}^4+a_6{r}^6+a_8{r}^8+a_{10}{r}^{10}+a_{12}{\mathrm{<figure-callout\; label="r"\; filenames="H2006101577350E00011.png"\; state="\{\{state\}\}">r</figure-callout>}}^{12},$ Among them, z is the axial value starting from the intersection of each aspheric surface and the optical axis and perpendicular to the optical axis direction, k is the quadratic surface coefficient, c is the curvature of the mirror center, r is the height of the mirror center; a2, a4, a6, a8 , a10, and a12 are aspherical coefficients; the optical lens satisfies the following relationship:

1.25＜f/L＜1.4；1.25<f/L<1.4;

0.5＜f1/f＜0.8；0.5<f1/f<0.8;

f2＜0且0.65＜|f2/f|＜1；f2<0 and 0.65<|f2/f|<1;

1.3＜f3/f＜1.6；1.3<f3/f<1.6;

其中，f为光学镜头的有效焦距值；f1为第一镜片的有效焦距值；f2为第二镜片的有效焦距值；f3为第三镜片的有效焦距值；L为空气换算距离后的光学镜头总长。Among them, f is the effective focal length value of the optical lens; f1 is the effective focal length value of the first lens; f2 is the effective focal length value of the second lens; f3 is the effective focal length value of the third lens; L is the optical lens after air conversion distance total length.

优选地，Preferably,

所述二次曲面系数的取值范围为：-20＜二次曲面系数＜20，所述曲率c的取值范围为：-10＜曲率c＜10，所述非球面系数a4、a6、a8、a10的取值范围为-10到10之间，所述非球面系数a2＝a12＝0。The value range of the quadratic surface coefficient is: -20<quadratic surface coefficient<20, the value range of the curvature c is: -10<curvature c<10, the aspheric surface coefficients a4, a6, a8 The value range of , a10 is between -10 and 10, and the aspheric coefficient a2=a12=0.

所述第一、二、三镜片的材质为塑料，所述第一、三镜片采用的材料相同，1.4＜所述第一、三镜片的折射率＜所述第二镜片的折射率＜1.6，所述第一、三镜片的色散值-所述第二镜片的值＞25。The material of the first, second and third mirrors is plastic, and the materials used for the first and third mirrors are the same, 1.4<refractive index of the first and third mirrors<refractive index of the second mirror<1.6, The dispersion value of the first and third lenses - the value of the second lens>25.

所述第一、二、三镜片的总长度介于3mm到4mm之间，且第一镜片和第二镜片之间的间距小于第二镜片和第三镜片之间的间距，所述每个镜片的中心厚度介于0.5mm与1.5mm之间。The total length of the first, second and third mirrors is between 3mm and 4mm, and the distance between the first mirror and the second mirror is smaller than the distance between the second mirror and the third mirror, each of the mirrors The center thickness is between 0.5mm and 1.5mm.

还包括位于第一镜片前靠近物方的固定光阑和位于第三镜片后远离物方的滤光片，该滤光片是一平板玻璃，包括与第三镜片相邻的第一平行板面和与成像面相邻的第二平行板面。It also includes a fixed diaphragm located in front of the first lens close to the object side and a filter located behind the third lens away from the object side, the filter is a flat glass, including a first parallel plate surface adjacent to the third lens and a second parallel plate plane adjacent to the imaging plane.

所述光学镜头的参数如下：The parameters of the optical lens are as follows:

镜片参数：Lens parameters:

非球面系数：Aspherical Coefficient:

  类型  K  a2  a4  a6  a8  a10  a12  第一非球面  -0.40588681  0  0.374181476  0.381297  -0.724601167  0.530543669  0  第二非球面  1.734715472  0  0.010349781  0.415246  -0.327398119  0.108775533  0  第三非球面  -7.0789132  0  -0.008248181  -0.00846  0.006579001  -0.00172741  0  第四非球面  -5.95078969  0  -0.028600059  -0.00056  0.002335316  -0.000638863  0 。 type K a2 a4 a6 a8 a10 a12 first aspheric surface -0.40588681 0 0.374181476 0.381297 -0.724601167 0.530543669 0 second aspheric surface 1.734715472 0 0.010349781 0.415246 -0.327398119 0.108775533 0 third aspheric surface -7.0789132 0 -0.008248181 -0.00846 0.006579001 -0.00172741 0 Fourth aspheric surface -5.95078969 0 -0.028600059 -0.00056 0.002335316 -0.000638863 0 .

所述光学镜头的参数如下：The parameters of the optical lens are as follows:

镜片参数：Lens parameters:

非球面系数：Aspherical Coefficient:

  类型 type  KK  a2a2  a4a4  a6a6  a8a8  a10a10  a12a12  第一非球面The first aspheric surface  -0.39475073-0.39475073  00  0.3710809470.371080947  0.3767380.376738  -0.721534761-0.721534761  0.5373805430.537380543  00  第二非球面The second aspheric surface  1.5951003971.595100397  00  0.0162104650.016210465  0.4089440.408944  -0.331695439-0.331695439  0.1114509870.111450987  00  第三非球面The third aspheric surface  -7.20657859-7.20657859  00  -0.011165615-0.011165615  -0.00777-0.00777  0.0068940570.006894057  -0.002021152-0.002021152  00  第四非球面The fourth aspheric surface  -6.44685466-6.44685466  00  -0.027274396-0.027274396  -0.00035-0.00035  0.0022118170.002211817  -0.000716067-0.000716067  00

。.

所述光学镜头的参数如下：The parameters of the optical lens are as follows:

镜片参数：Lens parameters:

非球面系数：Aspherical Coefficient:

  类型  K  a2  a4  a6  a8  a10  a12  第一非球面  -0.39475073  0  0.371080947  0.376738  -0.721534761  0.537380543  0  第二非球面  1.595100397  0  0.016210465  0.408944  -0.331695439  0.111450987  0  第三非球面  -7.20657859  0  -0.011165615  -0.00777  0.006894057  -0.002021152  0  第四非球面  -6.44685466  0  -0.027274396  -0.00035  0.002211817  -0.000716067  0。 type K a2 a4 a6 a8 a10 a12 first aspheric surface -0.39475073 0 0.371080947 0.376738 -0.721534761 0.537380543 0 second aspheric surface 1.595100397 0 0.016210465 0.408944 -0.331695439 0.111450987 0 third aspheric surface -7.20657859 0 -0.011165615 -0.00777 0.006894057 -0.002021152 0 Fourth aspheric surface -6.44685466 0 -0.027274396 -0.00035 0.002211817 -0.000716067 0 .

所述光学镜头的参数如下：The parameters of the optical lens are as follows:

镜片参数：Lens parameters:

非球面系数：Aspherical Coefficient:

  类型  K  a2  a4  a6  a8  a10  a12  第一非球面  -0.524391  0  0.450535  0.177664  -0.467706  0.341112  0  第二非球面  -0.806593  0  0.086624  0.289196  -0.247574  0.073675  0  第三非球面  -12.747824  0  0.019703  -0.035670  0.017661  -0.003234477  0  第四非球面  -9.391397  0  0.011322  -0.031091  0.010527  -0.001272875  0。 type K a2 a4 a6 a8 a10 a12 first aspheric surface -0.524391 0 0.450535 0.177664 -0.467706 0.341112 0 second aspheric surface -0.806593 0 0.086624 0.289196 -0.247574 0.073675 0 third aspheric surface -12.747824 0 0.019703 -0.035670 0.017661 -0.003234477 0 Fourth aspheric surface -9.391397 0 0.011322 -0.031091 0.010527 -0.001272875 0 .

本发明与现有技术相比的有益效果是：本发明的光学镜头在缩短镜头总长的基础上，确保适当的后焦距，还可以对各像差，特别是非点像差和畸变像差进行良好矫正，并得到理想的光学性能。Compared with the prior art, the present invention has the beneficial effects that: the optical lens of the present invention ensures an appropriate back focus on the basis of shortening the total length of the lens, and can also perform well on various aberrations, especially astigmatism and distortion aberrations. Correction, and get the ideal optical performance.

本发明的光学镜头成像质量好、总长短、亮度高、视场角大、出射角小、最低相对照度在50％以上、小巧轻薄、光学性能好。The optical lens of the invention has the advantages of good imaging quality, short overall length, high brightness, large viewing angle, small exit angle, minimum relative illuminance above 50%, compactness, lightness, and good optical performance.

本发明的光学镜头通过对非球面系数的优化，来修正各种像差，也可避免因采用球面镜而产生的球面像差，改善了成像品质。该光学镜头的总长小于6mm，使其模组可很容易的整合在手机模组中，满足了手机微型化的要求；因其采用全塑料材质，加工简单，降低了加工成本，同时增强了其抗冲击性。它适配于百万象素计以上的CCD，CCMOS成像器件，适用于小型数码相机，高象素手机等中。The optical lens of the present invention corrects various aberrations by optimizing the aspheric coefficients, and also avoids the spherical aberration caused by adopting spherical mirrors, thereby improving the imaging quality. The total length of the optical lens is less than 6mm, so that the module can be easily integrated in the mobile phone module, which meets the requirements of the miniaturization of the mobile phone; because it is made of all plastic material, the processing is simple, the processing cost is reduced, and its strength is enhanced. impact resistance. It is suitable for CCD and CCMOS imaging devices with more than one million pixels, suitable for small digital cameras, high-pixel mobile phones, etc.

本发明的光学镜头包括位于第一镜片前靠近物方的固定光阑，该光阑置于前方，能使镜头结构简单，紧凑，总长小；且由于镜片形状及镜头结构设计独特，有效校正了像差，从而提升了成像质量，分辨率，相对照度；同时全塑结构也大大降低了生产成本。The optical lens of the present invention includes a fixed aperture near the object side in front of the first lens, and the aperture is placed in the front, which can make the lens structure simple, compact and small in total length; Aberrations, thereby improving the imaging quality, resolution, and relative illumination; at the same time, the all-plastic structure also greatly reduces production costs.

附图说明Description of drawings

下面结合具体实施方式并对照附图对本发明进一步说明。The present invention will be further described below in combination with specific embodiments and with reference to the accompanying drawings.

图1是本发明的光学镜头的结构示意图；Fig. 1 is the structural representation of optical lens of the present invention;

图2是本发明的具体实施方式一的光学镜头的镜头MTF图；Fig. 2 is the lens MTF figure of the optical lens of embodiment one of the present invention;

图3是本发明的具体实施方式一的光学镜头的场曲示意图；Fig. 3 is a schematic diagram of the field curvature of the optical lens according to Embodiment 1 of the present invention;

图4是本发明的具体实施方式一的光学镜头的镜头横轴色差示意图。FIG. 4 is a schematic diagram of the lens transverse axis chromatic aberration of the optical lens according to Embodiment 1 of the present invention.

具体实施方式Detailed ways

如图1所示的光学镜头，从物方依次包括同轴的第一镜片1、第二镜片2、第三镜片3；第一镜片1为双凸球面正透镜，包括第一球面11和第二球面12；第二镜片2为具有负屈光度的非球面透镜，包括第一非球面21和第二非球面22，；第三镜片3为表面具有弓状的非球面正透镜，包括第三非球面31和第四非球面32。所述镜片形状皆沿光轴轴对称，其材质皆为塑料。Optical lens as shown in Figure 1, comprises coaxial first eyeglass 1,second eyeglass 2, the third eyeglass 3 successively from object side; Twospherical surfaces 12; thesecond lens 2 is an aspheric lens with negative diopter, including afirst aspheric surface 21 and asecond aspheric surface 22; the third lens 3 is an aspheric positive lens with a bow shape on the surface, including a third aspheric surface aspherical surface 31 and a fourth aspherical surface 32 . The shapes of the lenses are symmetrical along the optical axis, and the materials are all plastic.

所述第一镜片1和第三镜片3所采用采用的材料相同，其折射率定义为n1，色散值定义为v2；第二镜片2的折射率定义为n2，色散值定义为v2；其中n1、n2、v1、v2满足条件：1.4＜n1；n2＜1.6；n2＞n1；v1-v2＞25。其中，第一镜片1和第三镜片3优选使用环状烯烃共聚高分子材料(Thermoplastic Olefin Polymer of Amorphous Structure，TOPAS)，折射率n1＝1.53，色散v1＝54。所述第二镜片2优选使用聚碳酸酯(POLYCARB)材料，折射率n2＝1.585，色散v2＝29.5。The first lens 1 and the third lens 3 are made of the same material, their refractive index is defined as n1, and the dispersion value is defined as v2; the refractive index of thesecond lens 2 is defined as n2, and the dispersion value is defined as v2; where n1 , n2, v1, v2 satisfy the conditions: 1.4<n1; n2<1.6; n2>n1; v1-v2>25. Among them, the first lens 1 and the third lens 3 are preferably made of cyclic olefin copolymer polymer material (Thermoplastic Olefin Polymer of Amorphous Structure, TOPAS), the refractive index n1=1.53, and the dispersion v1=54. Thesecond lens 2 is preferably made of polycarbonate (POLYCARB) material, the refractive index n2=1.585, and the dispersion v2=29.5.

上述第一非球面21，第二非球面22，第三非球面31，第四非球面32，的形状皆满足以下的非球面公式：The shapes of thefirst aspheric surface 21, thesecond aspheric surface 22, the thirdaspheric surface 31, and the fourth aspheric surface 32 all satisfy the following aspheric surface formula:

$\mathrm{<span><span>z</span>z</span>}<span><span>=</span>=</span>\frac{{\mathrm{<span><span>cr</span><figure-callout\; label="cr"\; filenames="H2006101577350E00011.png"\; state="\{\{state\}\}">cr</figure-callout></span>}}^{\mathrm{<span><span>2</span>2</span>}}}{\mathrm{<span><span>1</span>1</span>}<span><span>+</span>+</span>\sqrt{\mathrm{<span><span>1</span>1</span>}<span><span>-</span>-</span><span><span>(</span>(</span>\mathrm{<span><span>1</span>1</span>}<span><span>+</span>+</span>\mathrm{<span><span>k</span>k</span>}<span><span>)</span>)</span>{\mathrm{<span><span>c</span>c</span>}}^{\mathrm{<span><span>2</span>2</span>}}{\mathrm{<span><span>r</span><figure-callout\; label="r"\; filenames="H2006101577350E00011.png"\; state="\{\{state\}\}">r</figure-callout></span>}}^{\mathrm{<span><span>2</span>2</span>}}}}<span><span>+</span>+</span>{\mathrm{<span><span>a</span>a</span>}}_{\mathrm{<span><span>1</span>1</span>}}{\mathrm{<span><span>r</span><figure-callout\; label="r"\; filenames="H2006101577350E00011.png"\; state="\{\{state\}\}">r</figure-callout></span>}}^{\mathrm{<span><span>2</span>2</span>}}<span><span>+</span>+</span>{\mathrm{<span><span>a</span>a</span>}}_{\mathrm{<span><span>2</span>2</span>}}{\mathrm{<span><span>r</span><figure-callout\; label="r"\; filenames="H2006101577350E00011.png"\; state="\{\{state\}\}">r</figure-callout></span>}}^{\mathrm{<span><span>4</span>4</span>}}<span><span>+</span>+</span>{\mathrm{<span><span>a</span>a</span>}}_{\mathrm{<span><span>3</span>3</span>}}{\mathrm{<span><span>r</span>r</span>}}^{\mathrm{<span><span>6</span>6</span>}}<span><span>+</span>+</span>{\mathrm{<span><span>a</span>a</span>}}_{\mathrm{<span><span>4</span>4</span>}}{\mathrm{<span><span>r</span>r</span>}}^{\mathrm{<span><span>8</span>8</span>}}<span><span>+</span>+</span>{\mathrm{<span><span>a</span>a</span>}}_{\mathrm{<span><span>5</span>5</span>}}{\mathrm{<span><span>r</span>r</span>}}^{\mathrm{<span><span>10</span>10</span>}}<span><span>+</span>+</span>{\mathrm{<span><span>a</span>a</span>}}_{\mathrm{<span><span>6</span>6</span>}}{\mathrm{<span><span>r</span><figure-callout\; label="r"\; filenames="H2006101577350E00011.png"\; state="\{\{state\}\}">r</figure-callout></span>}}^{\mathrm{<span><span>12</span>12</span>}}<span><span>.</span>.</span><span><span>.</span>.</span><span><span>.</span>.</span><span><span>.</span>.</span><span><span>.</span>.</span><span><span>.</span>.</span>$

其中：z为以各非球面与光轴交点为起点且垂直光轴方向的轴向值，即镜面深度值，因所选的镜片形状为轴对称式，故该非球面公式均取偶次项。k为二次曲面系数，即镜片的锥度；c为镜面中心曲率，c＝1/R，其中R为镜面中心曲率半径；r为镜面中心高度；a1、a2、a3、a4为非球面系数。上述二次曲面系数K的取值范围为-20＜K＜20，曲率c的取值范围为-10＜c＜10，所述非球面系数a4、a6、a8、a10的取值范围为-10到10之间，所述非球面系数a2＝a12＝0。Among them: z is the axial value starting from the intersection point of each aspheric surface and the optical axis and perpendicular to the optical axis direction, that is, the mirror depth value. Since the selected lens shape is axisymmetric, the aspheric surface formula takes an even term. . k is the quadratic surface coefficient, that is, the taper of the lens; c is the curvature of the center of the mirror, c=1/R, where R is the radius of curvature of the center of the mirror; r is the height of the center of the mirror; a1, a2, a3, a4 are aspheric coefficients. The value range of the above-mentioned quadratic surface coefficient K is -20<K<20, the value range of the curvature c is -10<c<10, and the value range of the aspheric coefficients a4, a6, a8, a10 is - Between 10 and 10, the aspheric coefficient a2=a12=0.

满足上述取值范围的光学镜头，其镜片表面面形不会发生特别急剧的改变，没有面形陡峭之处。在达到较好成像效果的同时能避免光线在各面上的入射角过大(主光线与表面法线间的角度)，一定程度上消除了发生鬼影，眩光的可能性。For an optical lens that meets the above value range, the surface shape of the lens will not change sharply, and there is no steepness of the surface shape. While achieving a better imaging effect, it can avoid excessive incident angles of light on each surface (the angle between the chief ray and the surface normal), and to a certain extent eliminate the possibility of ghosting and glare.

该光学镜头还可包括位于第一镜片1前靠近物方的固定光阑5。该光学镜头还可包括位于第三镜片3后远离物方的滤光片4。该滤光片4是一平板玻璃，包括与第一平行板面41与第二平行板面42。所述第一平行板面41与第三镜片3相邻，所述第二平行板面与成像面5相邻。所述滤光片4优选使用由熔融纯净原材料制成的硼硅酸炎玻璃材料，折射率n4＝1.5168，色散v4＝64.2。优选地，滤光片4至少一表面镀覆一层红外截止滤膜(IR-cut Coating)，以滤除来自于被摄物反射光线中的红外光线，从而提高成像质量。The optical lens may also include a fixeddiaphragm 5 located in front of the first lens 1 and close to the object side. The optical lens may further include afilter 4 behind the third lens 3 and away from the object. Theoptical filter 4 is a flat glass, including a firstparallel plate surface 41 and a secondparallel plate surface 42 . The firstparallel plate surface 41 is adjacent to the third lens 3 , and the second parallel plate surface is adjacent to theimaging surface 5 . Thefilter 4 is preferably made of borosilicate glass material made of molten pure raw materials, with a refractive index n4=1.5168 and a dispersion v4=64.2. Preferably, at least one surface of thefilter 4 is coated with a layer of infrared cut-off filter film (IR-cut Coating), to filter out the infrared light from the reflected light of the subject, thereby improving the imaging quality.

上述光学镜头满足以下条件：The above optical lens meets the following conditions:

1.25＜f/L＜1.41.25<f/L<1.4

0.5＜f1/f＜0.80.5<f1/f<0.8

f2＜0且0.65＜|f2/f|＜1f2<0 and 0.65<|f2/f|<1

1.3＜f3/f＜1.61.3<f3/f<1.6

其中：f为光学镜头的有效焦距值；f1为第一镜片1的有效焦距值；f2为第二镜片2的有效焦距值；f3为第三镜片3的有效焦距值；L为空气换算距离后的系统总长Among them: f is the effective focal length value of the optical lens; f1 is the effective focal length value of the first lens 1; f2 is the effective focal length value of thesecond lens 2; f3 is the effective focal length value of the third lens 3; L is after air conversion distance total system length

满足上述条件式后，可以在缩短镜头总长的基础上，确保适当的后焦距，还可以对各像差，特别是非点像差和畸变像差进行良好矫正，并得到理想的光学性能。After satisfying the above conditional formula, it is possible to ensure an appropriate back focus on the basis of shortening the total length of the lens, and to perform good correction of various aberrations, especially astigmatism and distortion aberration, and to obtain ideal optical performance.

本发明的光学镜头有效焦距为3.7，相对孔径为F/#＝2.8。该第一，第二及第三镜片1，2，3的总长度介于3mm到4mm之间。第一镜片1和第二镜片2之间的间距小于第二镜片2和第三镜片3之间的间距。每个镜片的中心厚度介于0.5mm与1.5mm之间。The effective focal length of the optical lens of the present invention is 3.7, and the relative aperture is F/#=2.8. The total length of the first, second andthird lenses 1, 2, 3 is between 3mm and 4mm. The distance between the first mirror 1 and thesecond mirror 2 is smaller than the distance between thesecond mirror 2 and the third mirror 3 . The center thickness of each lens is between 0.5mm and 1.5mm.

具体实施方式一、二、三、四出了基于上述结构构成的实施方式的具体参数值。其中，曲率半径是指各面与光轴相交的曲面的曲率半径；距值是指由物方沿光轴指向像方从某一面到与其相邻的下一面的距离；有效口径是各面的最大有效通光口径。这些具体参数的单位都为毫米(mm)。Specific Embodiments 1, 2, 3, and 4 show the specific parameter values of the implementations based on the above structures. Among them, the radius of curvature refers to the radius of curvature of the surface where each surface intersects the optical axis; the distance value refers to the distance from the object side to the image side along the optical axis from a certain surface to the next adjacent surface; the effective aperture is the distance of each surface The maximum effective aperture. The units of these specific parameters are millimeters (mm).

具体实施方式一：Specific implementation mode one:

所述光学镜头的参数如下：The parameters of the optical lens are as follows:

镜片参数：Lens parameters:

非球面系数：Aspherical Coefficient:

  类型 type  KK  a2a2  a4a4  a6a6  a8a8  a10a10  a12a12  第一非球面The first aspheric surface  -0.40588681-0.40588681  00  0.3741814760.374181476  0.3812970.381297  -0.724601167-0.724601167  0.5305436690.530543669  00

  类型 type  KK  a2a2  a4a4  a6a6  a8a8  a10a10  a12a12  第二非球面The second aspheric surface  1.7347154721.734715472  00  0.0103497810.010349781  0.4152460.415246  -0.327398119-0.327398119  0.1087755330.108775533  00  第三非球面The third aspheric surface  -7.0789132-7.0789132  00  -0.008248181-0.008248181  -0.00846-0.00846  0.0065790010.006579001  -0.00172741-0.00172741  00  第四非球面The fourth aspheric surface  -5.95078969-5.95078969  00  -0.028600059-0.028600059  -0.00056-0.00056  0.0023353160.002335316  -0.000638863-0.000638863  00

。.

对于具体实施方式一的镜头，其光学性能图见图2、3、4。图2是镜头的镜头光学调制传递函数曲线(MTF)，图中各线表示在不同视场及各视场的子午视场(T)和弧矢视场(S)的MTF，从图中可知各视场的MTF都非常集中，说明该光学镜头从中心到边缘视场的成像质量都很均匀，即整个图像都非常清晰。图3是镜头场曲示意图，其中光线A1、A2是波长为486.1327nm的蓝光，光线B1、B2是波长为587.5618nm的绿光，光线C1、C2是波长为656.2725nm的红光，从图中可知，该镜头的成像点很集中。图4是镜头横轴色差示意图，图中自左向右依次表示在486.1327nm、587.5618nm、656.2725nm三种不同波长时的色差情况，可知在这三种波长下该光学镜头的色差很小。For the lens of specific embodiment 1, its optical performance diagrams are shown in Figures 2, 3 and 4. Figure 2 is the optical modulation transfer function curve (MTF) of the lens. The lines in the figure represent the MTF of the meridional field of view (T) and the sagittal field of view (S) in different fields of view and each field of view. It can be seen from the figure The MTF of each field of view is very concentrated, indicating that the imaging quality of the optical lens is very uniform from the center to the edge of the field of view, that is, the entire image is very clear. Figure 3 is a schematic diagram of lens field curvature, where light rays A1 and A2 are blue light with a wavelength of 486.1327nm, light rays B1 and B2 are green light with a wavelength of 587.5618nm, and light rays C1 and C2 are red light with a wavelength of 656.2725nm. It can be seen that the imaging points of this lens are very concentrated. Figure 4 is a schematic diagram of chromatic aberration on the horizontal axis of the lens. The chromatic aberration at three different wavelengths of 486.1327nm, 587.5618nm, and 656.2725nm is shown in sequence from left to right in the figure. It can be seen that the chromatic aberration of the optical lens is very small at these three wavelengths.

具体实施方式二：Specific implementation mode two:

所述光学镜头的参数如下：The parameters of the optical lens are as follows:

镜片参数：Lens parameters:

非球面系数：Aspherical Coefficient:

  类型 type  KK  a2a2  a4a4  a6a6  a8a8  a10a10  a12a12  第一非球面The first aspheric surface  -0.39475073-0.39475073  00  0.3710809470.371080947  0.3767380.376738  -0.721534761-0.721534761  0.5373805430.537380543  00  第二非球面The second aspheric surface  1.5951003971.595100397  00  0.0162104650.016210465  0.4089440.408944  -0.331695439-0.331695439  0.1114509870.111450987  00

  类型 type  KK  a2a2  a4a4  a6a6  a8a8  a10a10  a12a12  第三非球面The third aspheric surface  -7.20657859-7.20657859  00  -0.011165615-0.011165615  -0.00777-0.00777  0.0068940570.006894057  -0.002021152-0.002021152  00  第四非球面The fourth aspheric surface  -6.44685466-6.44685466  00  -0.027274396-0.027274396  -0.00035-0.00035  0.0022118170.002211817  -0.000716067-0.000716067  00

。.

具体实施方式三：Specific implementation mode three:

所述光学镜头的参数如下：The parameters of the optical lens are as follows:

镜片参数：Lens parameters:

非球面系数：Aspherical Coefficient:

  类型 type  KK  a2a2  a4a4  a6a6  a8a8  a10a10  a12a12  第一非球面The first aspheric surface  -0.39475073-0.39475073  00  0.3710809470.371080947  0.3767380.376738  -0.721534761-0.721534761  0.5373805430.537380543  00  第二非球面The second aspheric surface  1.5951003971.595100397  00  0.0162104650.016210465  0.4089440.408944  -0.331695439-0.331695439  0.1114509870.111450987  00  第三非球面The third aspheric surface  -7.20657859-7.20657859  00  -0.011165615-0.011165615  -0.00777-0.00777  0.0068940570.006894057  -0.002021152-0.002021152  00  第四非球面The fourth aspheric surface  -6.44685466-6.44685466  00  -0.027274396-0.027274396  -0.00035-0.00035  0.0022118170.002211817  -0.000716067-0.000716067  00

。.

具体实施方式四：Specific implementation mode four:

所述光学镜头的参数如下：The parameters of the optical lens are as follows:

镜片参数：Lens parameters:

非球面系数：Aspherical Coefficient:

  类型  K  a2  a4  a6  a8  a10  a12  第一非球面  -0.524391  0  0.450535  0.177664  -0.467706  0.341112  0  第二非球面  -0.806593  0  0.086624  0.289196  -0.247574  0.073675  0  第三非球面  -12.747824  0  0.019703  -0.035670  0.017661  -0.003234477  0  第四非球面  -9.391397  0  0.011322  -0.031091  0.010527  -0.001272875  0。 type K a2 a4 a6 a8 a10 a12 first aspheric surface -0.524391 0 0.450535 0.177664 -0.467706 0.341112 0 second aspheric surface -0.806593 0 0.086624 0.289196 -0.247574 0.073675 0 third aspheric surface -12.747824 0 0.019703 -0.035670 0.017661 -0.003234477 0 Fourth aspheric surface -9.391397 0 0.011322 -0.031091 0.010527 -0.001272875 0 .

以上内容是结合具体的优选实施方式对本发明所作的进一步详细说明，不能认定本发明的具体实施只局限于这些说明。对于本发明所属技术领域的普通技术人员来说，在不脱离本发明构思的前提下，还可以做出若干简单推演或替换，都应当视为属于本发明由所提交的权利要求书确定的专利保护范围。The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and it cannot be assumed that the specific implementation of the present invention is limited to these descriptions. For those of ordinary skill in the technical field of the present invention, without departing from the concept of the present invention, they can also make some simple deduction or replacement, which should be regarded as belonging to the patent of the present invention determined by the submitted claims. protected range.

Claims (9)

1. optical lens comprises first and second and prismatic glasses of arranged in co-axial alignment, and the surface of described first eyeglass is a sphere, described second and the surface of prismatic glasses be aspheric surface, described second and the surface configuration of prismatic glasses satisfy as minor function:

Wherein, z is for being the axial axial value of starting point and vertical light with each aspheric surface and optical axes crosspoint, and k is the quadric surface coefficient, and c is the minute surface curvature of centre, and r is the minute surface centre-height; A2, a4, a6, a8, a10, a12 are asphericity coefficient;

It is characterized in that:

This optical lens satisfies following relational expression:

1.25＜f/L＜1.4；

0.5＜f1/f＜0.8；

F2＜0 and 0.65＜| f2/f|＜1;

1.3＜f3/f＜1.6；

Wherein, f is the effective focal length value of optical lens; F1 is the effective focal length value of first eyeglass; F2 is the effective focal length value of second eyeglass; F3 is the effective focal length value of prismatic glasses; L is the optical lens length overall behind the air scaled distance.

2. optical lens according to claim 1 is characterized in that:

The span of described quadric surface coefficient is :-20＜quadric surface coefficient＜20, the span of described curvature c is :-10＜curvature c＜10, the span of described asphericity coefficient a4, a6, a8 and a10 is-10 to 10, described asphericity coefficient a2=a12=0.

3. optical lens according to claim 1 and 2 is characterized in that:

The material of described first and second and prismatic glasses is plastics, described first is identical with the material of prismatic glasses employing, 1.4＜described first and refractive index＜1.6 of refractive index＜described second eyeglass of prismatic glasses, value＞25 of the dispersion values of described first and third eyeglass-described second eyeglass chromatic dispersion.

4. optical lens according to claim 3 is characterized in that:

To between the 4mm, and the spacing between first eyeglass and second eyeglass is less than the spacing between second eyeglass and the prismatic glasses between 3mm for the total length of described first and second and prismatic glasses, and the center thickness of described each eyeglass is between 0.5mm and 1.5mm.

5. optical lens according to claim 4 is characterized in that:

Away from the optical filter of object space, this optical filter is a sheet glass, comprises first parallel-plate face adjacent with prismatic glasses and the second parallel-plate face adjacent with imaging surface after also comprising the fixed aperture that is positioned at the preceding close object space of first eyeglass and being positioned at prismatic glasses.

6. optical lens according to claim 5 is characterized in that:

Described first eyeglass comprises first sphere and second sphere, and described second eyeglass comprises first aspheric surface and second aspheric surface, and described prismatic glasses comprises the 3rd aspheric surface and the 4th aspheric surface;

The parameter of described optical lens is as follows:

Lens parameters:

Asphericity coefficient:

Type K a2 a4 a6 a8 a10 a12First aspheric surface -0.40588681 0 0.374181476 0.381297 -0.724601167 0.530543669 0Second aspheric surface 1.734715472 0 0.010349781 0.415246 -0.327398119 0.108775533 0The 3rd aspheric surface -7.0789132 0 -0.008248181 -0.00846 0.006579001 -0.00172741 0The 4th aspheric surface -5.95078969 0 -0.028600059 -0.00056 0.002335316 -0.000638863 0

。

7. optical lens according to claim 5 is characterized in that:

Described first eyeglass comprises first sphere and second sphere, and described second eyeglass comprises first aspheric surface and second aspheric surface, and described prismatic glasses comprises the 3rd aspheric surface and the 4th aspheric surface;

The parameter of described optical lens is as follows:

Lens parameters:

Asphericity coefficient:

Type K a2 a4 a6 a8 a10 a12First aspheric surface -0.39475073 0 0.371080947 0.376738 -0.721534761 0.537380543 0Second aspheric surface 1.595100397 0 0.016210465 0.408944 -0.331695439 0.111450987 0The 3rd aspheric surface -7.20657859 0 -0.011165615 -0.00777 0.006894057 -0.002021152 0The 4th aspheric surface -6.44685466 0 -0.027274396 -0.00035 0.002211817 -0.000716067 0

。

8. optical lens according to claim 5 is characterized in that:

Described first eyeglass comprises first sphere and second sphere, and described second eyeglass comprises first aspheric surface and second aspheric surface, and described prismatic glasses comprises the 3rd aspheric surface and the 4th aspheric surface;

The parameter of described optical lens is as follows:

Lens parameters:

Asphericity coefficient:

Type K a2 a4 a6 a8 a10 a12First aspheric surface -0.39475073 0 0.371080947 0.376738 -0.721534761 0.537380543 0Second aspheric surface 1.595100397 0 0.016210465 0.408944 -0.331695439 0.111450987 0The 3rd aspheric surface -7.20657859 0 -0.011165615 -0.00777 0.006894057 -0.002021152 0The 4th aspheric surface -6.44685466 0 -0.027274396 -0.00035 0.002211817 -0.000716067 0

。

9. optical lens according to claim 5 is characterized in that:

Described first eyeglass comprises first sphere and second sphere, and described second eyeglass comprises first aspheric surface and second aspheric surface, and described prismatic glasses comprises the 3rd aspheric surface and the 4th aspheric surface;

The parameter of described optical lens is as follows:

Lens parameters:

Asphericity coefficient:

Type K a2 a4 a6 a8 a10 a12First aspheric surface -0.524391 0 0.450535 0.177664 -0.467706 0.341112 0Second aspheric surface -0.806593 0 0.086624 0.289196 -0.247574 0.073675 0The 3rd aspheric surface -12.747824 0 0.019703 -0.035670 0.017661 -0.003234477 0The 4th aspheric surface -9.391397 0 0.011322 -0.031091 0.010527 -0.001272875 0

。

Images