OPTICAL SYSTEM

An optical system is provided. The optical system includes a holder and a first compensation assembly. The holder is connected to an optical module. The first compensation assembly compensates a light. The first compensation assembly includes a first optical element. The light enters the optical module through the first compensation assembly.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to an optical system, in particular to an optical system with two compensation assemblies.

Description of the Related Art

With the development of technology, many electronic devices (such as tablet computers or smartphones) are equipped with an optical system to take pictures or record videos. Shaking may occur when a user uses an electronic device equipped with an optical system, and this may cause the images to come out blurry. Therefore, with the increasingly higher requirements for image quality, how to design a small and improved optical system is an important issue.

BRIEF SUMMARY OF THE INVENTION

An embodiment of the present invention provides an optical system. The optical system includes a holder and a first compensation assembly. The holder is connected to an optical module. The first compensation assembly compensates a light. The light enters the optical module through the first compensation assembly.

According to some embodiments of the present invention, the first compensation assembly includes a first optical element. The first optical element includes a substrate, a first microstructure and a second microstructure. The substrate is made of a light-transmitting material. The first microstructure is disposed on the substrate. The second microstructure is disposed on the substrate. The first microstructure is different from the second microstructure.

According to some embodiments of the present invention, the first optical element has a center. The first microstructure is closer to the center of the first optical element than the second microstructure when viewed along a direction perpendicular to the substrate.

According to some embodiments of the present invention, the substrate includes a central region. The central region is free of any microstructures

According to some embodiments of the present invention, the area of the central region is at least 10% of the area of the substrate.

According to some embodiments of the present invention, the central region at least partially overlaps the center of the optical module when viewed along a direction perpendicular to the substrate.

According to some embodiments of the present invention, the substrate includes a surface with a planar structure. The first microstructure includes a plurality of first microelements. The second microstructure includes a plurality of second microelements. Each of the first microelements has the same structure. Each of the second microelements has the same structure. The first microelements and the second microelements have different sizes.

According to some embodiments of the present invention, each of the first microelements has a cylindrical structure.

According to some embodiments of the present invention, the height of the first microelements and the second microelements are the same. The height of the first microelements or the second microelements is at least two times to three times larger than its width.

According to some embodiments of the present invention, the first compensation assembly further includes a fixed portion, a first movable portion and a first driving assembly. The first movable portion is connected to a first optical element. The first driving assembly is configured to drive the first movable portion to move between a first position and a second position relative to the fixed portion. The light enters the optical module through the first optical element when the first movable portion is in the first position, the light enters the optical module without passing through the first optical element when the first movable portion is in the second position.

According to some embodiments of the present invention, optical system further includes a second compensation assembly. The second compensation assembly compensates the light. The light enters the optical module through the second compensation assembly. The second compensation assembly includes a second movable portion and a second driving assembly. The second movable portion is connected to a second optical element. The second driving assembly is configured to drive the second movable portion to move relative to the fixed portion within a range of motion. The light enters the optical module through the second optical element when the second movable portion is located at any position in the range of motion.

According to some embodiments of the present invention, the second optical element is a lens, and the second driving assembly is configured to drive the second optical element to move relative to the fixed portion.

According to some embodiments of the present invention, the second optical element is a photosensitive element in the optical module, and the second driving assembly is configured to drive the second optical element to move relative to the fixed portion.

According to some embodiments of the present invention, the first compensation assembly and the second compensation assembly are disposed sequentially in the direction of the light, so that the light first passes through the first compensation assembly and then passes through the second compensation assembly, then enters the optical module. The area of the first optical element is smaller than the second optical element.

According to some embodiments of the present invention, the second compensation assembly and the first compensation assembly are disposed sequentially in the direction of the light, so that the light first passes through the second compensation assembly and then passes through the first compensation assembly, then enters the optical module. The area of the first optical element is larger than the second optical element.

According to some embodiments of the present invention, the optical system further includes a control element. The control element determines a mode from a non-compensation mode, a first compensation mode and a second compensation mode, to compensate the light. The first driving assembly and the second driving assembly are not driven during the non-compensation mode. The second driving assembly is driven to move the second movable portion during the first compensation mode. The first driving assembly is driven to move the first movable portion and the second driving assembly is driven to move the second movable portion during the second compensation mode. One of the non-compensation mode, the first compensation mode, and the second compensation mode is determined by the control element according to environmental conditions.

According to some embodiments of the present invention, the optical system further includes an inertial sensing element. The inertial sensing element outputs a sensing signal. The optical system determines the mode from the non-compensation mode, the first compensation mode, and the second compensation mode according to the sensing signal.

According to some embodiments of the present invention, the second compensation mode is activated when a rotation signal in the sensing signal is greater than a rotation preset value.

According to some embodiments of the present invention, the optical system further includes a sensing element. The first compensation mode is activated when a sensing signal that is greater than the first preset value is received, wherein the sensing signal is output by the sensing element.

According to some embodiments of the present invention, the second compensation mode is activated when a sensing signal that is greater than the second preset value is received, wherein the sensing signal is output by the sensing element.

DETAILED DESCRIPTION OF THE INVENTION

The following disclosure provides many different embodiments, or examples, for implementing different features of the provided subject matter. Specific examples of elements and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It should be appreciated that each term, which is defined in a commonly used dictionary, should be interpreted as having a meaning conforming to the relative skills and the background or the context of the present disclosure, and should not be interpreted in an idealized or overly formal manner unless defined otherwise.

Use of ordinal terms such as “first”, “second”, etc., in the claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another or the temporal order in which acts of a method are performed, but are used merely as labels to distinguish one claim element having a certain name from another element having the same name (but for use of the ordinal term) to distinguish the claim elements. The various embodiments disclosed herein are not necessarily limited by the illustrated ordering of acts or events, as some acts may occur in different orders and/or concurrently with other acts or events. Furthermore, not all illustrated acts or events are necessarily required to implement certain aspects and features of the present disclosure.

FIG.1shows a perspective view of an optical system10with a place-in-front configuration of a first compensation assembly100according to some embodiments. The optical system10includes the first compensation assembly100and a second compensation assembly200.

The place-in-front configuration of the first compensation assembly100refers to a configuration in which the first compensation assembly100is place before the second compensation assembly200along an optical axis O.

Therefore, the light first passes through the first compensation assembly100, and then passes through the second compensation assembly200to an optical module (FIG.6). The structure of the optical system10is described in detail later.

FIG.2Ashows a perspective view of the first compensation assembly100according to some embodiments.FIG.2Bshows an exploded view of the first compensation assembly100according to some embodiments. It is noted that the first compensation assembly100shown inFIG.2AandFIG.2Bis only provided for illustrative propose, and therefore should not be taken as a limitation.

As shown inFIG.2AandFIG.2B, the first compensation assembly100includes a fixed portion110, a first movable portion120, the first optical element130, a first driving assembly140, and an electrical connecting portion150.

In some embodiments of the present disclosure, the fixed portion110includes a cover111, a base112, and a plate113. The cover111is connected with the base112to accommodate the other elements of the first compensation assembly100.

The cover111includes four openings1111,1112,1113, and1114and an edge1115(FIG.4B), the details of which are describe later. The base112includes an upper surface1121, four protrusions1122,1123,1124,1125, and two accommodating spaces1126and1127.

The upper surface1121faces the cover111. The protrusions1122and1123extend along the optical axis O from the upper surface1121. The protrusion1124extends from the accommodating space1126. The protrusion1125extends from the accommodating space1127.

The base112and the plate113are connected to the second compensation assembly200(FIG.1). The plate113is disposed between cover111and the upper surface1121of the base112. The plate113includes four openings1131,1132,1133, and1134. The opening1111of the cover111is aligned with the opening1131of the plate113. The light passes through the opening1111of the cover111and the opening1131of the plate113.

The protrusion1122of the base112passes through the opening1132of the plate113and the opening1112of the cover111, to position the cover111and the plate113. The protrusion1123of the base112passes through the opening1133of the plate113and the opening1113of the cover111, to position the cover111and the plate113. The protrusion1124of the base112passes through the opening1134of the plate113and the opening1114of the cover111.

In some embodiments of the present disclosure, the first movable portion120is disposed between the cover111and the plate113. The first movable portion120is movable relative to the fixed portion110. The first movable portion120includes two openings121and122, a first edge123(FIG.4A) and two second edges124and125(FIG.4B), the details of which are described below.

The opening121holds the first optical element130. In some embodiments of the present disclosure, the first optical element130is a Metalens. Please briefly refer toFIG.3AandFIG.3B.FIG.3Ashows a schematic view of the first optical element130.FIG.3Bshows a schematic cross-sectional view of the first optical element130.

The first optical element130includes a substrate131, a first microstructure132, a second microstructure133, a third microstructure134, and a center135. The substrate131is made of a light-transmitting material. The first microstructure132, the second microstructure133, and the third microstructure134are disposed on the substrate131.

It is noted that the first optical element130may have more microstructure, such as a fourth microstructure and a fifth microstructure, but for the purpose of illustration, only the first microstructure132, the second microstructure133, and the third microstructure134are mentioned inFIG.3AandFIG.3B.

The center135is located in the center of the substrate131. The first microstructure132is closer to the center135than the second microstructure133when viewed along a direction perpendicular to the substrate131.

The substrate131includes a central region1311and a surface1312. The central region1311is a circular area that is free of any microstructures. The area of the central region is at least 10% of the area of the substrate131. The central region1311at least partially overlaps the center135of the optical module (FIG.6) when viewed along a direction perpendicular to the substrate131. The surface1312is a planar structure.

The first microstructure132includes a plurality of first microelements1321perpendicular to the surface1312of the substrate131. The first microstructure132may be regarded as a ring-like structure formed by the first microelements1321around the outside of the central region1311.

Each of the first microelements1321has the same structure. Specifically, in some embodiments, each of the first microelements1321has the same-sized cylindrical structure as that shown inFIG.3AandFIG.3B. However, in other embodiments, each of the first microelements1321may have a structure whose shape is not cylindrical. For example, its shape may be a square column, an oval column, a triangular column, or a polygonal column.

Similarly, the second microstructure133includes a plurality of second microelements1331perpendicular to the surface1312of the substrate131. The second microstructure133may be regarded as a ring-like structure formed by the second microelements1331around the outside of the first microstructure132.

Each of the second microelements1331has the same structure. Specifically, in some embodiments, each of the second microelements1331has the same-sized cylindrical structure as that shown inFIG.3AandFIG.3B. However, in other embodiments, each of the second microelements1331may have a structure that is not cylindrical. For example, that structure may be a square column, an oval column, a triangular column, or a polygonal column.

Similarly, the third microstructure134includes a plurality of third microelements1341perpendicular to the surface1312of the substrate131. The third microstructure134may be regarded as a ring-like structure formed by the third microelements1341around the outside of the second microstructure133.

Each of the third microelements1341has the same structure. Specifically, in some embodiments, each of the third microelements1341has a cylindrical structure of the same size as that shown inFIG.3AandFIG.3B. However, in other embodiments, each of the third microelements1341may have a structure that is not cylindrical. For example, it may be a square column, an oval column, a triangular column, or a polygonal column.

The first microstructure132is different from the second microstructure133and the third microstructure134. Specifically, the diameter of the second microstructure133is larger than the diameter of the first microstructure132, and the diameter of the third microstructure134is larger than the diameter of the first microstructure132and the second microstructure133.

Please refer toFIG.3B, it is noted that for the purpose of illustration, the cross-sectional view inFIG.3Bonly shows two of the first microelements1321, two of the second microelements1331, and two of the third microelements1341.

As shown inFIG.3B, the width A1 of the first microelements1321is smaller than the width A2 of the second microelements1331and the width A3 of the third microelements1341. The width A2 of the second microelements1331is smaller than the width A3 of the third microelements1341.

As shown inFIG.3B, the first microelements1321and the second microelements1331and the third microelements1341share the same the height B. The ratio A1/B of the width A1 and height B of the first microelements1321is at least greater than ⅓ to ½.

Similarly, the ratio A2/B of the width A2 and height B of the second microelements1331is at least greater than ⅓ to ½, and the ratio A3/B of the width A3 and height B of the third microelements1341is at least greater than ⅓ to ½. That is to say, the height B of the first microelements1321or the second microelements1331or the third microelements1341is at least two times to three times larger than its width.

Now refer back toFIG.2AandFIG.2B, in some embodiments of the present disclosure, the first driving assembly140is configured to drive the first movable portion120to move between a first position and a second position relative to the fixed portion110, the details of which are described with respect toFIG.4AandFIG.4B.

In some embodiments of the present disclosure, the first driving assembly140includes a magnetic element141and a driving portion142. The magnetic element141is disposed in the accommodating space1126of the base112. The magnetic element141includes a positioning hole1411and a shaft1412.

The protrusion1124of the base112passes through the positioning hole1411of the magnetic element141, the opening1134of the plate113, the opening122of the first movable portion120, and the opening1114of the cover111, so that the magnetic element141is rotatable about the protrusion1124relative to the fixed portion110. Thereby, the first movable portion120may be driven by the magnetic element141to move relative to the fixed portion110.

The shaft1412of the magnetic element141passes through the opening1134of the plate113, the opening122of the first movable portion120, and the opening1114of the cover111. Thus, when the magnetic element141is driven by the driving portion142, the first movable portion120may be driven by the shaft1412of the magnetic element141.

The driving portion142is disposed in the accommodating space1127of the base112. The driving portion142includes a coil1421and a magnetically permeable element1422. The coil1421is wrapped around the magnetically permeable element1422. The protrusion1125of the base112positions the driving portion142by passes through a gap143form in the magnetically permeable element1422.

The magnetic element141and the driving portion142correspond to each other. Specifically, when a driving signal is applied to the driving portion142(for example, by applying an electric current through an external power source), a magnetic force is generated between the magnetic element141and the driving portion142. Thereby, the magnetic element141may be driven to rotate relative to the fixed portion110.

In some embodiments of the present disclosure, the electrical connecting portions150are partially embedded in the base112. The electrical connecting portions are electrical connected to the driving portion142and an external power source (not shown).

FIG.4Ashows a top view of the first compensation assembly100with the first movable portion120in the first position, for the propose of illustration, the cover111is shown in dash line.FIG.4Bshows a top view of the first compensation assembly100with the first movable portion120in the second position, for the propose of illustration, the cover111is shown in dash line.

As shown inFIG.4A, the opening1114of cover111includes two edges1116and1117. When the shaft1412is driven to move toward the edge1116, the edge123of the first movable portion120comes into contact with the protrusion1122of the base112, and the first optical element130aligns with the opening1111of the cover111. As such, the light enters the optical module (FIG.6) through the first optical element130when the first movable portion120is in the first position.

As shown inFIG.4B, when the shaft1412is driven to move toward the edge1117, the edge124of the first movable portion120comes into contact with the edge1115of the cover111, the edge125of the first movable portion120comes into contact with the protrusion1123of the base112, and the first optical element130does not align with the opening1111of the cover111. As such, the light enters the optical module without passing through the first optical element130when first movable portion120is in the second position.

FIG.5shows an exploded view of the optical system10with the place-in-front configuration of the first compensation assembly100according to some embodiments. Since the details of the first compensation assembly100are described in detail in relation toFIG.2AtoFIG.2B, the detailed description of the structure of the first compensation assembly100is omitted here. The detailed description of the structure of the second compensation assembly200is described below.

According to some embodiments of the present disclosure, the second compensation assembly200includes a fixed portion210, a second movable portion220, a frame230, a focusing driving assembly240, a second driving assembly250, a supporting assembly260, and a set of sensing elements270.

According to some embodiments of the present disclosure, the fixed portion210includes a housing211, a base212, and a circuit member213. The housing211is connected with the base212to form an accommodating space for other elements in the second compensation assembly200. The base212may also be a holder that is connected to the optical module (FIG.6). The base212is parallel to the circuit member213. The circuit member213is fixedly disposed on the base212.

According to some embodiments of the present disclosure, the second movable portion220is connected to a second optical element2. The second movable portion220is a holder that is movable in the optical axis O relative to the fixed portion210to adjust the posture or position of the second optical element2, thereby achieving the purpose of optical auto-focusing (AF).

The frame230is a movable portion that may drive the second movable portion220to move relative to the fixed portion210in the XY-plane, so as to adjust the posture or position of the second optical element2, thereby achieving the effect of optical image stabilization (OIS).

According to some embodiments of the present disclosure, the focusing driving assembly240includes a coil241and a set of magnetic elements242. The coil241is disposed on the second movable portion220. The magnetic elements242are disposed on the upper portion of the frame230.

The coil241and the magnetic elements242correspond to each other. Specifically, when a driving signal is applied to the coil241(for example, by applying an electric current through an external power source), a magnetic force is generated between the coil241and the magnetic elements242. Thereby, the second movable portion220may be driven to move along the optical axis O relative to the fixed portion210to achieve the effect of auto-focusing.

According to some embodiments of the present disclosure, the second driving assembly250is configured to drive the second movable portion220to move relative to the fixed portion210within a range of motion. It is noted that the light enters the optical module (FIG.6) through the second optical element2when the second movable portion220is located at any position in the range of motion.

The second driving assembly250includes a set of coils251and a set of magnetic elements252. The coils251are disposed on the circuit member213. The magnetic elements252are disposed on the lower portion of the frame230.

The coils251and the magnetic elements252correspond to each other. Specifically, when a driving signal is applied to the coils251(for example, by applying an electric current through an external power source), a magnetic force is generated between the coils251and the magnetic elements252. Thereby, the frame230may be driven to move the second movable portion220along the XY-plane to achieve the effect of optical image stabilization.

According to some embodiments of the present disclosure, the supporting assembly260includes an upper elastic element261, a lower elastic element262, and a set of suspension wires263. The second movable portion220is movably connected to the housing211via the upper elastic element261. The second movable portion220is movably connected to the frame230via the lower elastic element262.

Before a driving signal is applied to the focusing driving assembly240and the second driving assembly250, the upper elastic element261and the lower elastic element262keep the second movable portion220at an initial position relative to the fixed portion210.

The four suspension wires263are located at the four corners of the second compensation assembly200. One end of each suspension wires263is connected to the upper elastic element261. The other end of each suspension wires263is connected to the base212.

According to some embodiments of the present disclosure, the sensing elements270are disposed on the circuit member213. In some embodiments, the sensing elements270may serve as a control element. Specifically, the sensing elements270are all-in-one integrated circuits that each encapsulate a sensing integrated circuit and a control integrated circuit in the same package. The sensing elements270sense the position of the frame230relative to the fixed portion210, and then control the frame230to move to a desired position to achieve closed-loop control.

In some embodiments, the sensing elements may include, for example, a Hall effect sensor, a magnetoresistance effect sensor, a giant magnetoresistance effect sensor, a tunneling magnetoresistance effect sensor, or a fluxgate sensor or other sensing elements, depending on design requirements.

It should be appreciated that the present invention does not limit the number of magnetic elements and reference elements used for sensing. In different embodiments, different numbers of magnetic elements and reference elements for sensing may be included, depending on design requirements.

In some embodiments, the sensing elements270include inertial sensing elements outputting a sensing signal. In this instance, the optical system10determines the mode from a non-compensation mode, a first compensation mode, and a second compensation mode according to the sensing signal, the details of which is described relative toFIG.9.

FIG.6shows a schematic view of the optical system10of one embodiment in the present disclosure with the place-in-front configuration of the first compensation assembly100. Compared with the optical system10shown inFIG.1,FIG.6further shows an optical module1and an infrared filter (IR filter)3.

As shown inFIG.6, the first compensation assembly100and the second compensation assembly200are disposed sequentially in the direction of the light, so that the light first passes through the first compensation assembly100and then passes through the second compensation assembly200, then enters the optical module1. In the embodiment shown in theFIG.6, the area of the first optical element130is smaller than the second optical element2.

FIG.7shows a perspective view of an optical system10′ with a place-in-back configuration of the first compensation assembly100′ according to some embodiments.FIG.8shows a schematic view of the optical system10′ of one embodiment in the present disclosure with the place-in-back configuration of the first compensation assembly100′.

As shown inFIG.7andFIG.8, the second compensation assembly200′ and the first compensation assembly100′ are disposed sequentially in the direction of the light, so that the light first passes through the second compensation assembly200′ and then passes through the first compensation assembly100′, then enters the optical module1′. The area of the first optical element130′ is larger than the second optical element2′.

It should be noted that the present disclosure includes embodiments with various configurations, such as, when the second optical element2serves as a lens, the second driving assembly250may be designed to drive the second optical element2to move relative to the fixed portion110and210.

Alternatively, in other embodiments where the second optical element2serves as a photosensitive element in the optical module1, the second driving assembly250may be designed to drive the second optical element2to move relative to the fixed portion110and210.

FIG.9is a flow chart of determining the mode for compensating the light entering the optical system10. The optical system10includes a non-compensation mode, a first compensation mode, and a second compensation mode for compensating the light.

The mode for compensating the light entering the optical system10is selected from the non-compensation mode, the first compensation mode, and the second compensation mode according to environmental conditions.

According to some embodiments of the present disclosure, block910includes that a sensing signal is received from the sensing elements270. Block920includes that the control element (which is the sensing element270that include a control integrated circuit in the present invention) determines whether the sensing signal is greater than a first preset value. Block930includes that the control element determines the sensing signal is smaller than the first preset value, and the non-compensation mode is selected. The first driving assembly140and the second driving assembly250are not driven during the non-compensation mode.

According to some embodiments of the present disclosure, block940includes that the control element have determined the sensing signal is greater than the first preset value, and proceed to determine whether the sensing signal is greater than a second preset value. Block950includes that the control element determines the sensing signal is smaller than the second preset value, and the first compensation mode is activated. The second driving assembly250drives the second movable portion220to move during the first compensation mode.

According to some embodiments of the present disclosure, block960includes that the control element determines the sensing signal is greater than the second preset value, and the second compensation mode is activated. The first driving assembly140drives the first movable portion120to move and second driving assembly250drives the second movable portion220to move during the second compensation mode.

In addition, in the embodiments where the sensing elements270are inertial sensing element, the second compensation mode is activated when a rotation signal in the sensing signal is greater than a rotation preset value.

In summary, the optical system of the present disclosure has a first compensation assembly and a second compensation assembly. When the degree of shaking caused by external force is larger, the first compensating assembly and the second compensating assembly may both be used to compensate the image, so as to improve the relatively poor peripheral imaging effect of the image caused by only using optical image stabilization (OIS) to compensate the image in the prior art.