CN103345045B - High-image-quality micro optical lens with all-plastic lens structure - Google Patents

Abstract

The invention relates to a high-image quality micro optical lens with a full plastic lens structure, which comprises a bearing seat and a lens cone connected on the bearing seat, wherein a compression ring, a first lens and a second lens are sequentially arranged in a cavity of the lens cone from outside to inside, and a space ring is arranged between the first lens and the second lens; the first lens is a negative focal length lens, the first surface of the first lens facing the object space is an oblate aspheric surface, and the second surface facing the image space is a hyperbolic aspheric surface; the second lens is a positive focal length lens, and a first surface facing the object side of the second lens is a circular aspheric surface, and a second surface facing the image side of the second lens is a hyperbolic aspheric surface. The invention provides an optical lens which has 200 ten thousand pixels and ultrathin thickness and can be used for a touch screen with high sensitivity and more than 70-110 inches.

Description

A high-quality micro-optical lens with an all-plastic lens structure

【Technical field】

The invention relates to an infrared wide-angle optical lens, in particular to a micro-optical lens for high-pixel touch screen identification.

【Background technique】

The currently used touch screen recognition lenses generally have such disadvantages: relatively low pixels and large external dimensions. The current mainstream camera phones on the market are mainly low-profile lenses with 300,000 pixels and 40-inch screens. Their sensitivity and recognition range are not ideal. They can only be used on touch screens that require less sensitivity and less screens; Generally about 10mm.

The present invention has carried out a large number of improvements in order to overcome the above shortcoming.

【Content of invention】

The invention overcomes the disadvantages of the prior art and provides an optical lens with 2 million pixels and ultra-thin thickness, which can be used for high-sensitivity and touch screens larger than 70-110 inches.

In order to solve the above-mentioned technical problems that exist, the present invention adopts the following technical solutions:

A high-image-quality micro-optical lens with an all-plastic lens structure is characterized in that it includes a base 1 and a lens barrel 2 connected to the base, and a pressure ring 3 is sequentially arranged in the cavity of the lens barrel 2 from outside to inside , the first lens 4, the second lens 5, spacer ring 6 is arranged between the first and the second lens; Described first lens 4 is a negative focal length lens, and its first surface 41 towards the object side is oblate Aspherical surface, the second surface 42 towards the image side is a hyperbolic aspheric surface; the second lens 5 is a positive focal length lens, and its first surface 51 towards the object side is a circular aspheric surface, and the second surface 52 towards the image side is Hyperbolic aspheric surface.

A high-image-quality micro-optical lens with an all-plastic lens structure as described above is characterized in that the system element characteristics of the first lens 4 and the second lens 5 satisfy the following expression: -5<f1/f2<2, vd P1≤60, vd P2-vd P1≤40, where f1 is the focal length of the first lens, f2 is the focal length of the second lens, vdP1 is the dispersion coefficient of the first lens, and vd P2 is the dispersion coefficient of the second lens.

A high-quality micro-optical lens with an all-plastic lens structure as described above is characterized in that the aspherical surface shapes of the first lens and the second lens satisfy the following equation: Z=cy ² /{1+√ [1-(1+k)c ² y ² ]}+α ₁ y ² +α ₂ y ⁴ +α ₃ y ⁶ +α ₄ y ⁸ +α ₅ y ¹⁰ +α ₆ y ¹² +α ₇ y ¹⁴ + α ₈ y ¹⁶ ; in the formula, the parameter c is the curvature corresponding to the radius, y is the radial coordinate and its unit is the same as the lens length unit, k is the coefficient of the conic conic curve; when the k coefficient is less than -1, the surface curve is Hyperbola, when it is equal to -1, it is a parabola, when it is between -1 and 0, it is an ellipse, when it is equal to 0, it is a circle, and when it is greater than 0, it is an oblate circle; α ₁ to α ₈ represent the corresponding radial coordinates coefficient.

A high-image-quality micro-optical lens with an all-plastic lens structure as described above is characterized in that: the hyperbolic shape of the first lens towards the second aspheric surface on the image side requires its k coefficient to be less than -1, and the first lens The shape of the first aspheric surface facing the object side is an oblate aspheric surface, and its k coefficient is greater than 0; the first aspheric surface of the second lens facing the object side is an oblate aspheric surface, and the k coefficient is greater than 0. The aspherical shape of the second surface of the second lens facing the image side is hyperbolic, and its k coefficient is less than -1.

The above-mentioned high-quality micro-optical lens with all-plastic lens structure is characterized in that: the distance between the first lens and the second lens surface is H, where 0<H≤1mm.

The above-mentioned high-quality micro-optical lens with an all-plastic lens structure is characterized in that: the trimming shape around the periphery of the first lens is a racetrack shape.

A high-quality micro-optical lens with an all-plastic lens structure as described above is characterized in that: vd P1<30 is used for the first lens, and vdP1 is the dispersion coefficient of the first lens.

A high-quality micro-optical lens with an all-plastic lens structure as described above is characterized in that the radius of curvature of the second surface 52 of the second lens facing the image plane is less than 3 mm.

Compared with the prior art, the present invention has the following advantages:

1. The digital lens of the present invention can reach more than 2 million pixels in the infrared spectrum, while the existing micro digital lens generally has 300,000 pixels.

2. The thinnest thickness of the present invention can reach 1.8mm.

3. The present invention can realize wide-angle photography with a maximum viewing angle of 140 degrees.

4. The present invention has high sharpness and high sensitivity to the touch recognition environment.

【Description of drawings】

Fig. 1 is a schematic cross-sectional view of the present invention.

Fig. 2 is an exploded schematic diagram of the present invention.

【Detailed ways】

The present invention is described in detail below in conjunction with accompanying drawing:

As shown in Figure 1, a high-image-quality micro-optical lens with an all-plastic lens structure can be used for relatively cheap high-pixel CMOS photosensitive sheets, including a seat 1 and a lens barrel 2 connected to the seat. A pressure ring 3, a first lens 4, and a second lens 5 are sequentially arranged in the cavity from outside to inside, and a spacer ring 6 is arranged between the first and second lenses. The first lens 4 is a negative focal length lens, the first surface 41 facing the object side is an oblate aspheric surface, and the second surface 42 facing the image side is a hyperbolic aspheric surface. The second lens 5 is a positive focal length lens, the first surface 51 facing the object side is a circular aspheric surface, and the second surface 52 facing the image side is a hyperbolic aspheric surface. The shape of trimmed edges around the periphery of the first lens is a racetrack shape, that is, the first lens is designed to be trimmed in an arc shape.

The surface shape of the aspherical surface of the first lens 4 and the second lens 5 satisfies the following equation:

Z＝cy ² /{1+√[1-(1+k)c ² y ² ]}+α ₁ y ² +α ₂ y ⁴ +α ₃ y ⁶ +α ₄ y ⁸ +α ₅ y ¹⁰ +α ₆ y ¹² +α ₇ y ¹⁴ +α ₈ y ¹⁶ . In the formula, the parameter c is the curvature corresponding to the radius, y is the radial coordinate, and its unit is the same as the lens length unit, k is the coefficient of the conic conic curve; when the k coefficient is less than -1, the surface curve is a hyperbola, which is equal to - When it is 1, it is a parabola, when it is between -1 and 0, it is an ellipse, when it is equal to 0, it is a circle, and when it is greater than 0, it is an oblate circle; α ₁ to α ₈ represent the coefficients corresponding to each radial coordinate. Through the above parameters, the shape and size of the aspheric surfaces on the front and rear sides of the lens can be precisely set.

The hyperbolic shape of the second aspherical surface of the first lens 4 facing the image side requires its k coefficient to be less than -1, and the first aspheric surface of the first lens facing the object side has an oblate aspheric shape, and its k coefficient is Greater than 0. The first aspherical surface of the second lens 5 facing the object side is an oblate aspheric surface, and the k coefficient is greater than 0, and the second aspheric surface of the second lens facing the image side is hyperbolic in shape, and its k coefficient is less than -1 .

The characteristics of the first lens and the second lens system components satisfy the following expressions: -5<f1/f2<2, vd P1≤60, vd P2-vd P1≤40, where f1 is the focal length of the first lens, f2 is the focal length of the second lens, vd P2 is the dispersion coefficient of the second lens, and vdP1 is the dispersion coefficient of the first lens. In a more optimal manner, the first lens adopts a lens with vd P1<30.

In order to realize large-angle light imaging, it is necessary to reduce the distance between the first lens and the second lens as much as possible structurally, that is, in this embodiment, the distance between the first lens and the second lens surface is H, where 0 <H≤1mm.

The seat 1 fits on the outer circumference of the rear end of the lens barrel 2 , and the seat 1 and the lens barrel 2 are threaded and fixed.

In the cavity of the lens barrel and the seat, the rear portion of the second lens 5 is also provided with an infrared filter 7, and the light enters from the infrared filter 7, and the infrared filter has a certain protective effect on the CMOS photosensitive chip. , At the same time, it also filters out unnecessary light that affects the image quality, making the image more profitable and improving the sensitivity, and at the same time helping to improve the image contrast.

The diaphragm surface is located between the first lens and the second lens of the optical system, and the diaphragm is also the above-mentioned spacer 6, which can make the optical aperture of the lens of the system small and reduce the sensitivity of the system to the manufacturing tolerance of the lens eccentricity, so that the optical System miniaturization and easy mass production.

The second surface of the second lens facing the image plane is a hyperbolic aspheric surface with a curvature radius of less than 3mm, which can make the length of the entire lens as short as 4.5mm or less.

The first lens of the system has negative refractive power, and the second lens has positive refractive power, so that the optical system can realize wide-angle imaging.

The following is the design case of this optical lens:

Surface Data Summary:

Surface data details:

Surface OBJ Standard

Surface 1 Aspherical

Surface 2 Aspherical

Surface STO standard

Surface 4 Aspherical

Surface 5 Aspherical

Surface 6 standard

Surface 7 standard

Surface IMA standard

Claims (7)

1. A high-image-quality miniature optical lens of an all-plastic lens structure is characterized in that it comprises a seat (1) and a lens barrel (2) connected to the seat, in the cavity of the lens barrel (2) from the outside A pressure ring (3), a first lens (4), and a second lens (5) are sequentially arranged in the inside, and a spacer (6) is arranged between the first and second lenses; the first lens (4) It is a negative focal length lens, and its first surface (41) towards the object side is an oblate aspheric surface, and the second surface (42) towards the image side is a hyperbolic aspheric surface; the second lens (5) is a positive focal length lens, Its first surface (51) towards the object side is a circular aspheric surface, and the second surface (52) towards the image side is a hyperbolic aspheric surface, and the first lens adopts vd P1<30, and vdP1 is the value of the first lens Dispersion coefficient. 2. a kind of high image quality miniature optical lens of all plastic lens structure according to claim 1, it is characterized in that described first lens (4), the second lens (5) system element characteristic satisfies following expression: -5<f1/f2<2, vd P2-vd P1≤40, where f1 is the focal length of the first lens, f2 is the focal length of the second lens, vdP1 is the dispersion coefficient of the first lens, vd P2 is the second lens dispersion coefficient. 3. according to claim 1 and 2 described a kind of high image quality miniature optical lens of all plastic lens structure, it is characterized in that the aspheric surface shape of described first lens (4) and second lens (5) Satisfy the following equation: Z=cy ² /{1+√[1-(1+k)c ² y ² ]}+α ₁ y ² +α ₂ y ⁴ +α ₃ y ⁶ +α ₄ y ⁸ +α ₅ y ¹⁰ +α ₆ y ¹² +α ₇ y ¹⁴ +α ₈ y ¹⁶ ; in the formula, the parameter c is the curvature corresponding to the radius, y is the radial coordinate (its unit is the same as the lens length unit), and k is the cone 2 Subcurve coefficient; when the k coefficient is less than -1, the surface curve is a hyperbola, when it is equal to -1, it is a parabola, when it is between -1 and 0, it is an ellipse, when it is equal to 0, it is a circle, and when it is greater than 0, it is an oblate circle shape; α ₁ to α ₈ respectively represent the coefficients corresponding to each radial coordinate. 4. a kind of high image quality miniature optics lens of all plastic lens structure according to claim 3, it is characterized in that: the hyperbola of the first lens toward the aspherical surface of the second side of image side, requires its k coefficient to be less than- 1. The first aspherical surface of the first lens facing the object side is an oblate aspheric surface, and its k coefficient is greater than 0; the first aspheric surface of the second lens facing the object side is an oblate aspheric surface, and its k coefficient is is greater than 0, the aspherical shape of the second surface of the second lens facing the image side is hyperbolic, and its k coefficient is less than -1. 5. The high-image-quality micro-optical lens of a kind of all-plastic lens structure according to claim 1 or 2, is characterized in that: the distance between the first lens and the second lens mirror surface is H, wherein 0<H ≤1mm. 6 . The high-image-quality micro-optical lens with an all-plastic lens structure according to claim 1 or 2, characterized in that: the trimming shape around the periphery of the first lens is a racetrack shape. 7. according to claim 1 or 2 described a kind of high image quality micro optical lens of all plastic lens structure, it is characterized in that: the radius of curvature of the second surface (52) of described second lens toward image surface is less than 3mm .