CN205193304U - Moist liquid lens of electricity and applied this liquid lens's cell -phone, digital camera - Google Patents

Abstract

The utility model discloses an electrowetting liquid lens and a mobile phone and a digital camera using the liquid lens. The electrowetting liquid lens includes a container, an electrolyte liquid, and a non-electrolyte liquid. The electrolyte liquid and the non-electrolyte liquid are accommodated in the container and form an interface in the container. After the container is powered, the electrolyte liquid can be applying a voltage to change the shape of the interface, the inner wall of the container is provided with a first coating which has a weaker affinity for the electrolyte liquid than for the non-electrolyte liquid, the inner wall is also provided with There is a spacer for positioning the interface. The electrowetting liquid lens of the utility model uses a positioning grid to precisely position the interface, which can keep the interface unchanged within a certain voltage range, thereby achieving precise zooming and digital zooming, and can solve the problem of large droplet driving voltage and focal length. Issues with small changes.

Description

Electrowetting liquid lens and mobile phone and digital camera using the liquid lens

technical field

The utility model relates to the technical field of optical lenses, in particular to an electrowetting liquid lens and a mobile phone and a digital camera using the liquid lens.

Background technique

Variable focus lenses are widely used in integrated imaging devices such as mobile phones, cameras, and microscopes. The traditional zoom lens is composed of multiple lenses, and a mechanical device is used to adjust the relative position of the lenses to achieve the purpose of zooming. Therefore, complex structures, high energy consumption, and easy wear and tear have become the main disadvantages of traditional zoom systems. In order to overcome the above shortcomings, liquid zoom is a good way. There are three ways to realize liquid zoom: (1) change the internal refractive index of the variable focus liquid lens, and use physical and chemical methods to change internal parameters such as liquid density and transmittance; (2) ) Change the curvature of the liquid surface, and change the radius of curvature of the cavity surface by pressurizing the liquid surface to achieve continuous zooming; (3) Based on the electrowetting effect, change the liquid distribution inside the liquid lens to achieve overall deformation of the lens for focusing. Electrowetting variable focus liquid lens has the advantages of simple structure, low cost, low power consumption, long life, easy realization of array structure and integration, fast response speed, etc., so more and more people pay attention to it.

In recent years, many foreign scientific research institutions have made great achievements in electrowetting variable focus liquid lenses. In the prior art, the main disadvantages of the electrowetting variable focus liquid lens are concentrated in the following points: First, the ordinary tubular liquid lens can only change the focal length, the optical axis is unstable, the focal length cannot be precisely determined, and it is not easy to manufacture and carry out digital Control; Second, the driving voltage of the liquid lens using a large droplet is large and the focal length variation range is small.

Utility model content

The technical problem to be solved by the utility model is to provide an electrowetting liquid lens with stable optical axis, precise focal length, small driving voltage and large focal length variation range, and mobile phones and digital cameras using the liquid lens.

The technical solution adopted by the utility model to solve the problems of the technologies described above is:

The utility model provides an electrowetting liquid lens, comprising: a container, an electrolyte liquid and a non-electrolyte liquid, the electrolyte liquid and the non-electrolyte liquid are accommodated in the container and form an interface in the container, the container After electrification, a voltage can be applied to the electrolyte liquid to change the shape of the interface, and the inner wall of the container is provided with a first coating, and the affinity of the first coating to the electrolyte liquid is weaker than that to the electrolyte liquid. The affinity of the non-electrolyte liquid, the inner wall is also provided with a positioning lattice for positioning the interface.

As a further improvement of the above technical solution, a positioning layer is provided between the inner wall and the first coating, and the positioning layer is provided with an annular positioning wall, and the positioning lattice is formed between adjacent positioning walls.

As a further improvement of the above technical solution, a conductive layer is provided between the inner wall and the positioning layer.

As a further improvement of the above technical solution, the container includes a conductive cover plate, a conductive substrate, and a cavity tube placed between the conductive cover plate and the conductive substrate, and the conductive layer and the positioning layer are placed in the cavity tube between the wall and the first coat.

As a further improvement of the above technical solution, the first coating is coated with an insulating and hydrophobic material.

As a further improvement of the above technical solution, the conductive layer includes at least two electrodes separated along the axis of the container.

As a further improvement of the above technical solution, the positioning layer is a micron structure formed by a photolithography process.

The utility model provides a mobile phone, which comprises the above-mentioned electrowetting liquid lens.

The utility model also provides a digital camera, which includes the above-mentioned electrowetting liquid lens.

The beneficial effects of the utility model are:

The electrowetting liquid lens of the utility model uses a positioning grid to precisely position the interface, which can keep the interface unchanged within a certain voltage range, thereby achieving precise zooming and digital zooming, and can solve the problem of large droplet driving voltage and focal length. Issues with small changes.

The device adopting the electrowetting liquid lens of the utility model can also achieve precise and digital zooming effect, and the driving voltage is small and the focal length change range is large.

Description of drawings

Fig. 1 is a schematic structural view of the first embodiment of the electrowetting liquid lens of the present invention;

Fig. 2 is a schematic diagram of the electrode distribution of the first embodiment of the electrowetting liquid lens of the present invention;

Fig. 3 is a schematic structural view of the second embodiment of the electrowetting liquid lens of the present invention.

detailed description

The idea, specific structure and technical effects of the present utility model will be clearly and completely described below in conjunction with the embodiments and accompanying drawings, so as to fully understand the purpose, characteristics and effects of the present utility model. Apparently, the described embodiments are only some of the embodiments of the present utility model, rather than all embodiments. Based on the embodiments of the present utility model, other embodiments obtained by those skilled in the art without paying creative efforts, All belong to the protection scope of the utility model. In addition, all the connection/connection relationships involved in the patent do not simply refer to the direct connection of components, but mean that a better connection structure can be formed by adding or reducing connection accessories according to specific implementation conditions. Each technical feature in the utility model can be combined interactively under the premise of not conflicting with each other.

Fig. 1 and Fig. 2 show the specific structure of the first embodiment of the electrowetting liquid lens of the present invention. Please refer to FIG. 1 and FIG. 2 together. The electrowetting liquid lens of the present invention includes a container 11, an electrolyte liquid 12 and a non-electrolyte liquid 13. The electrolyte liquid 12 and the non-electrolyte liquid 13 are contained in the container 11 and An interface 14 is formed in the container 11 , and after the container 11 is powered on, a voltage can be applied to the electrolyte liquid 12 to change the shape of the interface 14 . The non-electrolyte liquid 13 may be an alkane like hexadecane or silicone oil or a mixture thereof, and the electrolyte liquid 12 may be water or a salt solution such as an aqueous sodium chloride solution.

The container 11 includes a conductive cover plate 11a, a conductive substrate 11b, and a cavity pipe 11c placed between the conductive cover plate 11a and the conductive substrate 11b, the inner wall of the cavity pipe 11c is provided with a first coating 15, the The affinity of the first coating 15 to the electrolyte liquid 12 is weaker than its affinity to the non-electrolyte liquid 13, and a conductive layer 17 and positioning layer 16, the positioning layer 16 refers to the positioning wall 16a arranged around the inner wall of the cavity pipe 11c, and a concave shape is formed between adjacent positioning walls 16a to position the interface 14 As a positioning grid, the first coating 15 is coated with an insulating hydrophobic material.

The material of the cavity tube 11c in this embodiment is preferably but not limited to glass, and may also be metal or flexible polymer, such as PET, PI, PDMS, PMMA and the like.

The first coating 15 is a single-layer insulating hydrophobic material, preferably AF1600, AF1601, AF1600X, Hyflon, Cytop or fluorinated polyimide and other surface hydrophobic insulating film materials; in different embodiments, the first The coating 15 can also be divided into two layers: an insulating layer and a hydrophobic layer, that is, a layer of dielectric material such as a silicon oxide layer or a silicon nitride layer is coated on the conductive layer 17, with a thickness of 10-500nm to form an insulating layer. ; Then coat a layer of 10-100nm hydrophobic material to form a hydrophobic layer. Of course, when the coated material meets the requirements of hydrophobicity and insulation at the same time, it can be directly coated to form an insulating hydrophobic layer.

The positioning grid 18 formed by micromachining corresponds to a voltage adjustment range. When the adjustment voltage is within this range, since the positioning grid 18 is on the order of microns, we can consider that the shape of the interface 14 remains unchanged at this time, thereby achieving the control of the liquid interface 14. Positioning function, so that digital zoom can be accurately realized.

The conductive layer 17 includes at least two electrodes separated along the axial direction of the container 11. In this embodiment, the conductive layer 17 is divided into four electrodes: a first electrode 17a, a second electrode 17b, a third electrode 17c and a fourth electrode 17a. Electrode 17d. The two incompatible liquids in the glass tube 11c form a surface shape as the first interface state 14a due to the difference in surface tension. After applying voltage, the voltage changes the interfacial tension between the two phases of oil and water, resulting in a change in the shape of the interface 14 , changing to the second interface state 14b. When the height of the positioning wall 16a is high, the liquid level remains unchanged after the voltage is removed. At this time, if the potential of the first electrode 17a is the highest, the interface 14 will deviate from the direction of the first electrode 17a, that is, using four electrodes Different potentials cause the interface to deviate in different directions, causing the interface to return to the first interface state 14a.

Fig. 3 shows the specific structure of the second embodiment of the electrowetting liquid lens of the present invention. The difference between this embodiment and the first embodiment is that the metal tube 21c is used instead of the glass tube, so that there is no need to coat the metal tube 21c with a conductive layer, and the first coating 25 is directly coated on the The surface of the metal pipe 21c is sufficient. Of course, in this embodiment, positioning walls 26a also need to be provided on the metal pipe 21c to form the positioning grid 28 .

The manufacturing method of the electrowetting liquid lens of the present utility model takes a glass tube as an example, as follows:

S1. Clean and dry the glass tube with an inner diameter of 0.1-10mm, an outer diameter of 0.2-20mm, and a height of 1-100mm.

S2. Dip the clean glass tube into the photoresist to form a photoresist film with a thickness of 1-10 microns on the inner tube wall, and the height of the positioning wall is realized by the different viscosities of the photoresist. The photoresist-coated glass tube was then dried at 65-95°C for 10-30 minutes and cooled to room temperature. Put the glass tube horizontally and contact with the mask plate and expose it to ultraviolet radiation. After the exposure, heat the quartz glass tube at 65-95 degrees Celsius for 10-30 minutes, and finally put the glass tube that has completed the above process in the developer solution. Developing in the middle, the developer dissolves the unexposed area, and the remaining positioning wall structure remains on the inner wall of the glass tube. The width of the wall is preferably 1-100 microns, and the distance between the walls is 1-100 microns.

S3. After the positioning wall is solidified, a conductive layer with a thickness of about 10-250nm is plated on the inner and outer walls of the glass tube as electrodes. It should be noted that there is no conductive layer within a certain distance from the lower end of the glass tube, as shown in Figure 1. 17. In particular, if a metal tube with an inner diameter of 0.1-10mm and an outer diameter of 0.2-20mm is used instead of a glass tube, the insulating and hydrophobic layer can be directly coated without making a conductive layer in advance.

S4. Use the dip coating method to immerse the glass tube in the fluoropolymer solution, so that the fluoropolymer forms a hydrophobic insulating layer with a thickness of about 0.5-1.5um on the inner and outer walls of the glass tube, as shown in Figure 1 First coat 15.

S5. Adhesively and firmly connect the above-mentioned glass tube and the conductive substrate with glue.

S6. Use a pipette gun to inject the electrolyte liquid into the bottom of the lens, and then extract the non-electrolyte liquid to fill the lens.

S7. Glue the device filled with liquid to the conductive glass cover.

The electrowetting liquid lens of the utility model is small in size, light in body and simple in structure, and can be applied in digital cameras, portable computers with built-in cameras or mobile phones, replacing traditional optical zoom components. Of course, the liquid lens of the present invention can be applied to vehicle camera sensors in the industrial field, industrial systems with barcode reading devices, and industrial endoscopes; television internal monitors and surveillance cameras in safe places.

It should be noted that electrowetting is also called electrowetting, and the utility model is also applicable to electrowetting liquid lenses.

The above is a specific description of the preferred implementation of the utility model, but the utility model is not limited to the embodiments, and those skilled in the art can also make various equivalent deformations without violating the spirit of the utility model Or replacement, these equivalent modifications or replacements are all included within the scope defined by the claims of the present application.

Claims (9)

1. electric wetting liquid lens, comprise: container, electrolytic liquid and nonelectrolyte liquid, electrolytic liquid and nonelectrolyte liquid to be placed in described container and to form an interface in described containers, voltage can be applied to change the shape at described interface to described electrolytic liquid after described container powers up, the inwall of described container is provided with the first coating, it is characterized in that: the compatibility of described first coating to described electrolytic liquid is weaker than its compatibility to described nonelectrolyte liquid, and described inwall is also provided with the positioning lattice played the role of positioning to described interface.

2. electric wetting liquid lens as claimed in claim 1, is characterized in that: be provided with alignment layers between described inwall and the first coating, and described alignment layers is provided with ring-type location wall, forms described positioning lattice between the wall of adjacent described location.

3. electric wetting liquid lens as claimed in claim 2, is characterized in that: be provided with conductive layer between described inwall and described alignment layers.

4. electric wetting liquid lens as claimed in claim 3, it is characterized in that: described container comprises conductive cover plate, electrically-conductive backing plate and is placed in the cavity pipe between described conductive cover plate and electrically-conductive backing plate, and described conductive layer and alignment layers are placed between described cavity inside pipe wall and the first coating.

5. the electric wetting liquid lens as described in any one of Claims 1-4, is characterized in that: described first coating is formed by insulating hydrophobic Material coating.

6. the electric wetting liquid lens as described in claim 3 or 4, is characterized in that: described conductive layer comprises at least two pieces of electrodes be separated along described container axis direction.

7. electric wetting liquid lens as claimed in claim 2, is characterized in that: described alignment layers is the micrometer structure adopting photoetching process to be formed.

8. a mobile phone, is characterized in that: comprise electric wetting liquid lens as claimed in claim 1.

9. a digital camera, is characterized in that: comprise electric wetting liquid lens as claimed in claim 1.