WO2019218323A1 - Lens array, imaging device, and imaging method - Google Patents

Abstract

The present invention discloses a lens array, an imaging device, and an imaging method. The imaging device comprises: a main lens for guiding imaging light rays; a lens array, located on a focal plane of the main lens, and at least comprising one lens unit; a sensor located on a focal plane of the lens array; and a control unit for controlling a focal length of the lens unit. The control unit adjusts the focal length of the lens unit, such that a camera mode of the imaging device is selectively activated.

Description

Lens array, imaging device and imaging method

[Technical Field]

The present invention relates to an imaging technique, and more particularly to a lens array, an imaging device, and an imaging method.

 【Background technique】

Light field camera (Light Field Camera) is a kind of data that records the beam in all directions when the user takes a picture. After taking the picture, the focus is processed by the computer, that is, the picture is taken first and then the focus is taken, and the user selects the focus condition by himself, and finally obtains a camera with a satisfactory photo, as opposed to The camera mode of the traditional camera eliminates the time spent focusing and inaccurate focus when taking pictures, making the picture more concise and fast. However, the existing light field camera captures light from all directions in the scene through a microlens array disposed in front of the sensor, so that the camera can only work in the light field camera mode, resulting in a low resolution of the resulting photo.

 [Summary of the Invention]

The technical problem to be solved by the present invention is to provide a lens array, an imaging device, and an imaging method, which can solve the image by using a lens array in the imaging device to enable the imaging device to select an ordinary camera mode, a light field camera mode, and a combination mode. Low resolution problem.

In order to solve the above technical problem, a technical solution adopted by the present invention is:

An imaging device is provided, comprising:

a main lens for conducting imaging light;

a lens array on a focal plane of the main lens, the lens array including at least one lens unit;

a sensor located on a focal plane of the lens array;

a control unit for controlling a focal length of the lens unit.

In order to solve the above technical problem, another technical solution adopted by the present invention is:

Providing an imaging method comprising:

The main lens receives ambient light and conducts the light to the lens array;

The lens array processes the ambient light and transmits the processed light to the sensor;

The sensor acquires the processed light, converts the optical image contained therein into an electrical signal, and delivers the electrical signal to the control unit;

The control unit parses the electrical signal to obtain an image, and sends a control instruction to the lens array by changing a focus requirement for the image, changing a curvature of the lens unit in the lens array, and completing focusing on a subsequent image. deal with.

In order to solve the above technical problem, another technical solution adopted by the present invention is:

A lens array is provided, comprising:

Substrate

a first electrode disposed on the substrate;

a hydrophobic insulating layer disposed on the first electrode, and the hydrophobic insulating layer is provided with a plurality of receiving grooves to expose the first electrode;

The receiving groove is configured to receive a light transmissive medium;

An elastic film is disposed on the transparent medium and the hydrophobic insulating layer;

a second electrode is disposed on the elastic film;

Forming, by the first electrode and the second electrode, a lens unit at a receiving groove, and by supplying a voltage to the first electrode and the second electrode, the first electrode and the second electrode are opposite to the receiving groove The lens unit forms a lens.

The beneficial effects of the present invention are: different from the prior art, the present invention controls the focal length of the lens unit in the lens array by the control unit by using a lens array in the imaging device, so that the imaging device selectively turns on the ordinary Camera mode, light field camera mode and combination mode to solve the problem of low image resolution.

 [Description of the Drawings]

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings to be used in the embodiments will be briefly described below. Obviously, the drawings in the following description are only some of the present invention. For the embodiments, those skilled in the art can obtain other drawings according to the drawings without any creative work.

1 is a schematic structural view of an image forming apparatus of the present invention;

2a is a schematic structural view of a lens array of the present invention;

2b is a schematic structural view of a lens unit in a lens array according to the present invention;

Figure 3 is a top plan view of a lens array of the present invention;

4 is a schematic structural view of a lens array and a sensor in an ordinary camera mode according to the imaging device of the present invention;

5 is a schematic structural view of a lens array and a sensor in an optical field camera mode of the imaging device of the present invention;

6 is a schematic structural view of a lens array and a sensor in which an imaging device of the present invention is combined with a common camera mode and a light field camera mode.

Figure 7 is a schematic flow chart of the image forming method of the present invention;

【Detailed ways】

The technical solutions in the embodiments of the present invention will be clearly and completely described in the following with reference to the accompanying drawings. The conflicts in the following embodiments may be combined with each other. It is apparent that the described embodiments are only a part of the embodiments of the invention, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

The teachings "including" and "having", and any variations thereof, are intended to cover a non-exclusive inclusion, such as a process or method comprising a series of steps or units. The system, product, or device is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not explicitly listed or inherent to such processes, methods, products, or devices.

1 is a schematic structural view of an image forming apparatus of the present invention, and the image forming apparatus includes:

a main lens 1 for conducting imaging light;

a lens array 2, located on the focal plane of the main lens 1, the lens array 2 includes at least one lens unit 100;

The control unit 3 is configured to control the focal length of the lens unit 100.

The sensor 4 is located on the focal plane of the lens array 2.

Specifically, the lens unit 100 is a liquid zoom lens or an electrowetting two-liquid zoom lens.

specific,

The lens array 2 as shown in FIG. 2a is a schematic structural view of a lens array of the present invention, and the lens array 2 includes:

Substrate 10;

a first electrode 20 disposed on the substrate 10;

a hydrophobic insulating layer 30 disposed on the first electrode 20, and the hydrophobic insulating layer 30 is provided with a plurality of receiving grooves 40 to expose the first electrode 20;

The receiving groove 40 is for accommodating the transparent medium 50;

An elastic film 60 is disposed on the transparent medium 50 and the hydrophobic insulating layer 30;

The elastic film 60 is placed on the second electrode 70;

The first electrode 20 and the second electrode 70 form a lens unit 100 at a position opposite to the receiving groove 40.

The plurality of receiving grooves 40 provided in the hydrophobic insulating layer 30 are a plurality of strip-shaped receiving grooves 40 penetrating the hydrophobic insulating layer 30;

The first electrode 20 is composed of a plurality of first electrode strips and is disposed corresponding to the receiving groove 40, and the second electrode 70 is composed of a plurality of second electrode strips;

The plurality of strip-shaped receiving grooves 40 are parallel to each other, the plurality of first electrode strips are parallel to each other, and the plurality of second electrode strips are parallel to each other;

A projection of the first electrode strip on a plane of the second electrode 70 perpendicularly intersects the second electrode strip to form a lens unit 100 at an intersection, and the shape of the lens unit 100 may be a diamond shape or a square shape. In the present embodiment, the shape of the lens unit 100 is not limited.

As shown in FIG. 2a, a transparent ITO (Indium Tin) is plated on the glass substrate 10. An Oxides, indium tin oxide film, as the first electrode 20, the first electrode 20 is uniformly distributed in parallel strips by a photolithographic method, and then coated on the first electrode strip A layer of hydrophobic insulating layer 30 is coated, and a parallel stripe-shaped spacer distribution corresponding to the shape of the first electrode strip is formed on the hydrophobic insulating layer 30, and the underlying layer of the hydrophobic insulating layer 30 is exposed. The first electrode strip is formed to form a receiving groove 40. A transparent medium 50 is placed in the receiving groove 40, and then a transparent elastic film 60 is deposited on the transparent medium 50 by chemical vapor deposition to encapsulate the transparent medium 50 in a closed space. Inside, the thickness of the transparent elastic film 60 is controlled to be about 1-2 μm to have appropriate elasticity. A transparent ITO film is further plated on the transparent elastic film 60 as the second electrode 70. The first electrode 20 and the second electrode 70 are separated by the hydrophobic insulating layer 30, the transparent medium 50, and the transparent elastic film 60. The first electrode 20 and the second electrode 70 form a lens unit 100 at a position opposite to the receiving groove 40.

2b is a schematic structural view of the lens unit 100 in a pressurized state in the lens array of the present invention. As can be seen from FIG. 2b, the first electrode 20 and the second electrode 70 are given by the control unit 3. Providing a voltage V, such as providing a positive voltage to one of the first or second electrodes, providing a negative voltage to the other, and controlling a voltage magnitude to adjust the focal length of the lens unit 100 such that the first electrode 20 is The second electrode 70 forms the lens 200 with respect to the lens unit 100 at the receiving groove.

In this embodiment, the transparent medium 50 is a transparent insulating liquid, and the formed lens array is a liquid lens array.

Since the periphery of the receiving groove 40 is the hydrophobic insulating layer 30, the transparent insulating liquid has a large contact angle with the hydrophobic insulating layer 30, so that the lens unit 100 is slightly convex as shown in FIG. 2a. a state (to facilitate understanding of macroscopic magnification), the second electrode 70 is also in a bent state, after a voltage V is applied between the first electrode 20 and the second electrode 70, due to the bending of the second electrode 70 The potential effect and the force between the first electrode 20 and the second electrode 70 deform the transparent medium 50 and the transparent elastic film 60 deposited on the surface of the transparent medium 50, thereby causing the lens The unit 100 forms a lens 200, and the magnitude of the voltage applied between the first electrode 20 and the second electrode 70 by the control unit 3 controls the surface curvature of the transparent medium 50, and adjusts the focal length of the lens unit 100. Achieve zoom.

Please refer to FIG. 3 , which is a schematic top view of the lens array of the present invention. The projection of the first electrode strip on the plane of the second electrode 70 perpendicularly intersects the second electrode strip to form a square lens unit 100 . .

In this embodiment, the first electrode 20 and the second electrode 70 are transparent indium tin oxide, or the first electrode 20 is transparent indium tin oxide, and the second electrode 70 is nanometer. silver.

In the image forming apparatus of the present invention,

When the control unit 3 does not supply a voltage to all of the lens units 100, the imaging device operates in a normal camera mode (i.e., a two-dimensional imaging mode) to obtain a normal two-dimensional image. In this mode, the lens unit 100 in the lens array 2 corresponds to one transparent plate, and the entire lens array 2 corresponds to a single transparent plate, which is equivalent to adding a transparent element to the imaging optical path of a general camera. After the object plane passes through the main lens 1 and the transparent element, the sensing unit 41 (shown in FIG. 4) is imaged on the sensor 4 to obtain a normal two-dimensional image. The transparent plate does not affect the imaging quality of the incident light at a small angle, and the astigmatism and the like are introduced to the concentrated or divergent light. In the present invention, although the light of the front main lens 1 directed to the lens array 2 is not nearly parallel. Light, but the aberration introduced by the plate element can be balanced in the design of the main lens 1 to control the aberration within an acceptable range.

When the control unit 3 supplies voltages to all of the lens units 100, adjusting the focal length of the lens unit 100 causes the imaging device to operate in a light field camera mode (i.e., a four-dimensional imaging mode) to obtain a light field image. In this mode, all of the lens units 100 in the lens array 2 are pressurized to form a lens 200, which conjugates the image plane of the main lens 1 with respect to the object plane onto the sensor 4 of the imaging device. The sensing unit 41 (shown in FIG. 5) satisfies the imaging requirements of the focused light field camera at this time, and the light field image is obtained on the image surface. By reprocessing the light field image data, images such as digital refocusing, extended depth of field, and the like can be obtained. Meanwhile, since there is a gap between the lenses 200 in the lens array 2, the imaging quality of these spaced regions cannot be ensured, and these intervals may cause grid-like noise on the image plane image. However, since the intervals are regularly distributed, and once the lens unit 100 is pressurized to become the lens 200, the structure of the lens array 2 is also determined, and the interval can be determined, and the interval is introduced on the image plane. Grid-like noise will also be determined. Therefore, these grid noises can be removed by image processing to remove the distribution pixels corresponding to these intervals.

When the control unit 3 supplies a voltage to a portion of the lens unit 100, adjusting the focal length of the lens unit 100 causes the imaging device to operate in a combined mode of a normal camera and a light field camera, that is, a local light field camera mode and In a partial normal camera mode, the partial lens unit 100 is pressurized to form a lens 200 that conjugates the image plane of the main lens 1 with respect to the object plane onto the sensing unit 41 on the sensor 4 of the imaging device, Satisfying the imaging requirements of the focused light field camera, the image field is obtained on the image surface, and the remaining lens unit 100 is equivalent to the transparent plate because it is not pressurized, and the image plane is imaged on the sensor 4 after passing through the main lens 1 and the transparent plate. On the sensing unit 41, a normal two-dimensional image is obtained (as shown in Fig. 6).

In this embodiment, the imaging device is a camera. In other embodiments, the imaging device can also be other types of electronic devices.

Please refer to FIG. 7 , which is a schematic flowchart of an imaging method of the present invention. The imaging method includes the following steps:

In step S1, the main lens 1 receives external light and conducts the light to the lens array 2.

In step S2, the lens array 2 processes the external light and transmits the processed light to the sensor 4.

In step S3, the sensor 4 acquires the processed light, converts the optical image contained therein into an electrical signal, and delivers the electrical signal to the control unit 3.

Step S4, the control unit 3 parses the electrical signal to obtain an image, and sends a control instruction to the lens array 2 by changing the focus requirement for the image to change the curvature of the lens unit 100 of the lens array 2. , complete the focus processing on subsequent images.

The lens array 2 is the lens array described in Figure 2a.

The control unit 3 does not provide voltage for all of the lens units 100, and the imaging device turns on the normal camera mode;

The control unit 3 supplies voltages to all of the lens units 100, and adjusts the focal length of the lens unit 100 to cause the imaging device to turn on the light field camera mode;

The control unit 3 supplies a voltage to a portion of the lens unit 100, and adjusts the focal length of the lens unit 100 to cause the imaging device to turn on a combination mode of a normal camera and a light field camera, that is, a local light field camera mode and a local normal camera mode. .

The imaging device can automatically adjust which positions need to enable the normal camera mode to acquire texture according to the scene content, and which positions need to enable the light field camera mode to detect the depth, and obtain the depth information of a certain point of the local point under the high resolution of the image.

The imaging device can be automatically adjusted according to the content of the scene as follows:

1. For static pictures, the automatic selection mode of the imaging device working mode:

1 Perform texture detection according to the image after imaging of the main lens to automatically select the working mode of the imaging device: in the same picture, the imaging device performs texture detection on all images in the image, and when the detected image mainly appears as image surface texture information, such as When the color, shape, position structure, etc., the imaging device turns on the normal camera mode for the corresponding image position; when the detected image mainly does not represent the image surface texture information as described above, the imaging device turns on the light for the corresponding image position. Field camera mode.

2 Perform edge detection according to the image after imaging of the main lens to automatically select the working mode of the imaging device: in the same picture, the imaging device performs edge detection on all images in the image, and the image mainly represents the depth between the detected image edge and the image. Distance information, such as distance, coverage, etc., the imaging device turns on the light field camera mode for the corresponding image position; when the detected image edge and the image mainly exhibit image depth distance information as described above, the imaging device The normal camera mode is turned on for the corresponding image position.

The above two image detection methods can be simultaneously performed in the same screen, and the working mode of the imaging device is automatically selected for different information of different screen representations. When the detected image mainly appears as image surface texture information, the imaging device opens the corresponding image position. The normal camera mode is described; when the detected image edge and the image mainly represent the image as depth distance information, the imaging device turns on the light field camera mode for the corresponding image position, and realizes a combination mode of the common imaging device and the light field camera of the same imaging device.

2. For dynamic pictures, the automatic selection mode of the imaging device working mode:

The first frame of the dynamic picture is detected according to the static picture image detection mode, and the imaging device further automatically selects an operation mode corresponding to the image position: when the detected image mainly appears as image surface texture information, the imaging device opens the corresponding image position. Ordinary camera mode; when the detected image edge and the image mainly represent the image as depth distance information, the imaging device turns on the light field camera mode for the corresponding image position.

The second frame of the dynamic image refers to the first frame image. The scene selectively detects the switching operation mode: the second frame picture and the first frame picture image have no change portion, and the imaging device does not perform image detection (the specific detection mode refers to the static picture imaging device) The automatic selection mode of the working mode) repeats the working mode selected after the first frame picture is automatically detected; the second frame picture and the first frame picture image change part, the imaging device performs image detection again, and selects the corresponding working mode. The third frame refers to the second frame, and the fourth frame refers to the third frame, and so on, the image detection and the automatic selection of the working mode of the imaging device are performed.

The present invention provides a voltage between the first electrode and the second electrode by providing a strip-shaped first electrode and a second electrode perpendicular to each other in the lens array, and a receiving groove including the exposed first electrode Forming a lens at a position corresponding to the first electrode and the second electrode to realize a free switching between a normal camera mode and a light field camera mode; realizing a local point light field camera mode acquisition, and acquiring a common camera mode of the remaining points; It is also possible to automatically adjust which positions need to enable the normal camera mode to obtain the image surface texture according to the scene content, and which positions need to enable the light field camera mode to detect the image depth distance, and obtain the depth distance information of a certain point of the local point under the image high resolution, thereby Solve the problem of low image resolution.

The above is only the embodiment of the present invention, and is not intended to limit the scope of the invention, and the equivalent structure or equivalent process transformations made by the description of the invention and the drawings are directly or indirectly applied to other related technologies. The fields are all included in the scope of patent protection of the present invention.

Claims (14)

1. An image forming apparatus, wherein the image forming apparatus comprises:

   a main lens for conducting imaging light;

   a lens array on a focal plane of the main lens, the lens array including at least one lens unit;

   a sensor located on a focal plane of the lens array;

   a control unit for controlling a focal length of the lens unit.
2. The image forming apparatus according to claim 1, wherein the lens unit is a liquid crystal zoom lens or an electrowetting two-liquid zoom lens.
3. The image forming apparatus according to claim 1, wherein said lens array comprises:

   Substrate

   a first electrode disposed on the substrate;

   a hydrophobic insulating layer disposed on the first electrode, and the hydrophobic insulating layer is provided with a plurality of receiving grooves to expose the first electrode;

   The receiving groove is configured to receive a light transmissive medium;

   An elastic film is disposed on the transparent medium and the hydrophobic insulating layer;

   a second electrode is disposed on the elastic film;

   A voltage is applied to the first electrode and the second electrode, and the first electrode forms a lens opposite to the second electrode.
4. The image forming apparatus according to claim 3, wherein the light transmitting medium is a transparent insulating liquid.
5. The image forming apparatus according to claim 3, wherein the plurality of receiving grooves provided on the hydrophobic insulating layer are a plurality of strip-shaped receiving grooves penetrating the hydrophobic insulating layer,

   The first electrode is composed of a plurality of first electrode strips and is disposed corresponding to the receiving groove, and the second electrode is composed of a plurality of second electrode strips.

   A projection of the first electrode strip on a plane of the second electrode intersects the second electrode strip.
6. The image forming apparatus according to claim 5, wherein said plurality of strip-shaped receiving grooves are parallel to each other, said plurality of first electrode strips are parallel to each other, and said plurality of second electrode strips are parallel to each other.
7. The image forming apparatus according to claim 5, wherein a projection of said first electrode strip on a plane on which said second electrode is located intersects said second electrode strip perpendicularly.
8. An imaging method, wherein the method comprises:

   The main lens receives ambient light and conducts the light to the lens array;

   The lens array processes the ambient light and transmits the processed light to the sensor;

   The sensor acquires the processed light, converts the optical image contained therein into an electrical signal, and delivers the electrical signal to the control unit;

   The control unit parses the electrical signal to obtain an image, and sends a control instruction to the lens array by changing a focus requirement for the image, changing a curvature of the lens unit in the lens array, and completing focusing on a subsequent image. deal with.
9. A lens array, wherein the lens array comprises:

   Substrate

   a first electrode disposed on the substrate;

   a hydrophobic insulating layer disposed on the first electrode, and the hydrophobic insulating layer is provided with a plurality of receiving grooves to expose the first electrode;

   The receiving groove is configured to receive a light transmissive medium;

   An elastic film is disposed on the transparent medium and the hydrophobic insulating layer;

   a second electrode is disposed on the elastic film;

   Forming, by the first electrode and the second electrode, a lens unit at a receiving groove, and by supplying a voltage to the first electrode and the second electrode, the first electrode and the second electrode are opposite to the receiving groove The lens unit forms a lens.
10. The lens array according to claim 9, wherein the plurality of receiving grooves provided on the hydrophobic insulating layer are a plurality of strip-shaped receiving grooves penetrating the hydrophobic insulating layer,

    The first electrode is composed of a plurality of first electrode strips and is disposed corresponding to the receiving groove, and the second electrode is composed of a plurality of second electrode strips.

    A projection of the first electrode strip on a plane of the second electrode intersects the second electrode strip.
11. The lens array according to claim 10, wherein the plurality of strip-shaped receiving grooves are parallel to each other, the plurality of first electrode strips are parallel to each other, and the plurality of second electrode strips are parallel to each other.
12. The lens array according to claim 10, wherein a projection of the first electrode strip on a plane of the second electrode intersects perpendicularly with the second electrode strip.
13. The lens array of claim 9, wherein the first and second electrodes are transparent indium tin oxide.
14. The lens array according to claim 9, wherein the first electrode is a transparent indium tin oxide and the second electrode is a nano silver.