Optical system

An optical system is provided, including an optical module, a fixed part, a movable part for holding an optical module, and a flexible member. The flexible member movably connects the movable part to the fixed part to suppress the vibration of the optical system at a first frequency.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to an optical system, and, in particular, to an optical system capable of shock absorption.

Description of the Related Art

As technology has advanced, a lot of electronic devices (for example, laptop computers and smartphones) have incorporated the functionality of taking photographs and recording video. These electronic devices have become more commonplace, and have been developed to be more convenient and thin. More and more options are provided for users to choose from.

In some electronic devices, several coils and magnets are usually used for adjusting the focus of a lens and performing the function of Optical Image Stabilization (OIS). Light can propagate through the lens to an image sensor, whereby a digital image is generated.

However, to increase the shock absorption capability of the optical system when used in vehicles can be difficult. Therefore, addressing the aforementioned problems has become a challenge.

BRIEF SUMMARY OF THE INVENTION

An embodiment of the present invention provides an optical system that includes a fixed part, a movable part for holding an optical module, and a flexible member. The flexible member connects the movable part to the fixed part for suppressing the vibration of the optical system at a first frequency.

In some embodiments, the flexible member comprises a steel cable, a spring or a combination thereof.

In some embodiments, the flexible member is disposed at a corner of the fixed part.

In some embodiments, the optical system further includes two flexible members disposed on opposite sides of the fixed part.

In some embodiments, the optical system further includes three flexible members disposed on different sides or at different corners of the fixed part.

In some embodiments, the fixed part has a quadrilateral structure, and the optical system further comprises four flexible members respectively disposed on the corners of the fixed part.

In some embodiments, the optical system further includes a circuit assembly, wherein the optical module has an optical element and an image sensing unit connected to each other, the circuit assembly is electrically connected to the image sensing unit, and the flexible member is electrically independent from the circuit assembly.

In some embodiments, the optical system further includes a circuit assembly, wherein the optical module has an optical element and an image sensing unit connected to each other, the circuit assembly is electrically connected to the image sensing unit, and the flexible member is electrically connected to the ground point of the circuit assembly.

In some embodiments, the optical system further includes a support structure affixed to the movable part and connected to the flexible member.

In some embodiments, the support structure forms a plurality of protrusions connected to the movable part.

In some embodiments, a recess is formed between the protrusions, and the flexible member is connected to the recess.

In some embodiments, the optical system further includes a spring connecting the movable part to the fixed part, wherein the spring surrounds the optical axis of the optical element.

In some embodiments, the optical system further includes a circuit assembly, wherein the optical module has an optical element and an image sensing unit connected to each other, the circuit assembly is electrically connected to the image sensing unit and extends through the spring.

In some embodiments, the optical system further includes a damper disposed between the fixed part and the movable part.

In some embodiments, the movable part has a holder, a frame, and an active damping mechanism, the holder is movably connected to the frame, and the active damping mechanism is disposed on the holder and the frame for suppressing the vibration of the optical system at a second frequency.

In some embodiments, the optical system further includes a connecting member, a plurality of clamps, and a plurality of ball elements disposed on the connecting member, wherein the clamps are respectively affixed to the holder and the frame, and the ball elements are clamped by the clamps.

In some embodiments, the optical system further includes a plurality of flexible members, wherein the fixed part has a quadrilateral structure, and the flexible members are disposed at the respective corners of the fixed part, wherein the clamps are located on different sides of the movable part, and each of the clamps is located between two of the flexible members.

In some embodiments, the active damping mechanism has a magnet disposed on the holder and a coil disposed on the frame.

In some embodiments, the active damping mechanism comprises a piezoelectric element or a shape memory alloy element connected between the holder and the frame.

In some embodiments, the optical system further includes a position sensor disposed on the holder or the frame to detect displacement between the holder and the frame.

In some embodiments, the optical system further includes a gyroscope disposed on the holder.

In some embodiments, the second frequency is less than the first frequency.

In some embodiments, the first frequency is greater than 1 Hz.

In some embodiments, the first frequency is greater than 10 Hz.

DETAILED DESCRIPTION OF THE INVENTION

In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings, and in which specific embodiments of which the invention may be practiced are shown by way of illustration. In this regard, directional terminology, such as “top,” “bottom,” “left,” “right,” “front,” “back,” etc., is used with reference to the orientation of the figures being described. The components of the present invention can be positioned in a number of different orientations. As such, the directional terminology is used for the purposes of illustration and is in no way limiting.

FIG.1is an exploded diagram of an optical system100, in accordance with an embodiment of the invention.FIG.2is a perspective diagram of the optical system100inFIG.1after assembly.FIG.3is a perspective diagram of the optical system100inFIG.2when the cover H2is omitted.FIG.4is a perspective diagram of the components inside the hosing H1ofFIG.3.FIG.5is an exploded diagram of the components inside the hosing H1ofFIG.3.FIG.6is a perspective diagram of the holder20, the frame30, and the connecting member40after assembly.FIG.7is an exploded diagram of the holder20, the frame30, and the connecting member40before assembly.FIG.8is a bottom view of the connecting member40that has four arms41pivotally connecting to the holder20and the frame30via the ball elements B and the clamps50.

Referring toFIGS.1-8, the optical system100may be a camera device that is disposed in a vehicle. In this embodiment, the optical system100primarily comprises an optical module10, a holder20, a frame30, a connecting member40, a plurality of clamps50, a circuit board60disposed on the outer surface of the frame30, a base70, a cable80, a housing H1, a cover H2connected to the housing H1, a plurality of magnets M, a plurality of ball elements B disposed on the connecting member40, a plurality of coils C disposed on the circuit board60, a circuit assembly P, a plurality of flexible members W, two support structures F1and F2, and a plurality of fasteners S.

It should be noted that the base70, the housing H1, and the cover H2constitute a fixed part of the optical system100, and the holder20and the frame30constitute a movable part of the optical system100. The movable part and the fixed part are movably connected to each other via the flexible members W, thereby suppressing the vibration of the optical system100owing to external forces and preventing the optical module10from being damaged.

In this embodiment, the holder20is movably received in the frame30, the magnets M are affixed in the recesses21of the holder20(FIGS.6and7), and the coils C are mounted to the circuit board60. When the coils C are energized, an electromagnetic force can be produced to rotate the holder20relative to the frame30around the X axis or the Y axis, thereby achieving Optical Image Stabilization (OIS) of the optical system100. For example, the circuit board60may be a flexible printed circuit (FPC) that surrounds the protrusions31of the frame30(FIGS.6and7).

The flat support structures F1and F2are respectively affixed to the base70and the frame30, and four flexible members W (e.g. steel cables) are connected between the two support structures F1and F2. The circuit assembly P includes two circuit boards P1, P2and a connecting circuit P3. The connecting circuit P3may be a flexible printed circuit (FPC) that electrically connects the circuit board P1to the circuit board P2.

The cable80is disposed at the bottom of the base70for electrically connecting the circuit board P1of the circuit assembly P to a power supply or a computer. The base70of the optical system100can be mounted to a vehicle (e.g. car, motorcycle or bicycle) by the fasteners S for photographing or video recording.

As shown inFIGS.6-8, the holder20and the frame30are movably connected to each other via the connecting member40. The connecting member40has four arms41and a round chassis42connected to the four arms41. In this embodiment, four ball elements B are disposed on the respective arms41and clamped in the four U-shaped clamps50.

Still referring toFIGS.7-8, several slots22and32are formed on the holder20and the frame30for receiving the clamps50. In this embodiment, two arms41of the connecting member40are connected to the holder20via the ball elements B and the clamps50in the slots22, and the other arms41of the connecting member40are connected to the frame30via the ball elements B and the clamps50in the slots32. Hence, the holder20can rotate relative to the frame30around the X axis or the Y axis to achieve Optical Image Stabilization (OIS) of the optical system100.

FIG.9is a cross-sectional view of the optical system100inFIG.2when the cover H2is omitted.FIG.10is another cross-sectional view of the optical system100inFIG.2when the cover H2is omitted.FIG.11is a cross-sectional view of the optical system100inFIG.2when the cover H2and the optical module10are omitted.FIG.12is a perspective diagram of the flexible members W connected between the two support structures F1and F2.

As shown inFIGS.9-10, the image sensing unit12has an image sensor121, a substrate122, and a connector123. The image sensor121is disposed on the substrate122, and the connector123electrically connects the substrate122to the circuit board P2of the circuit assembly P. Light can propagate through the optical element11to the image sensor121of the image sensing unit12, thereby generating a digital image. The digital image can be transmitted to a computer via the circuit assembly P and the cable80.

Referring toFIGS.9-12, the two support structures F1and F2may comprise metal or plastic material, wherein each of the support structures F1and F2has two hollow and flat plates. An end of the flexible member W is clamped between the two flat plates of the support structure F1, and the other end of the flexible member W is clamped between the two flat plates of the support structure F2.

FIGS.9-10further shows that at least a damper G (e.g. gel) is disposed between the housing10and the frame30, whereby collision between the housing10and the frame30can be avoided.

In this embodiment, the four flexible members W are disposed at the four corners of the quadrilateral base70. In some embodiments, the optical system100may have only one flexible member W that is disposed at a corner of the base70. In some embodiments, the optical system100may have two flexible members W disposed at two different corners or on opposite sides of the base70. In some embodiments, the optical system100may have three flexible members W disposed at three different corners or on three different sides of the base70. In some embodiments, the four flexible members W may be disposed on the four sides of the base70.

With the flexible members W connected between the base70and the frame30, the vibration of the optical system100at a first frequency can be efficiently suppressed, wherein the first frequency is greater than 1 Hz. Moreover,FIG.12shows that the support structure F2forms several protrusions F21affixed to the bottom of the frame30, and at least a recess F22is formed between two adjacent protrusions F21and connected to the flexible member W.

Here, the flexible member W can be used as a passive damper that is not electrically connected to the circuit assembly P. However, in some embodiments, the flexible member may be electrically connected to the ground point of the circuit assembly P.

With the magnets M and the coils C disposed on the holder20and the frame30, an electromagnetic force can be produced to rotate the holder20relative to the frame30. In some embodiments, however, the magnets M and the coils C may be replaced by a piezoelectric element or a shape memory alloy element that is connected between the holder20and the frame30for achieving Optical Image Stabilization (OIS) of the optical system100.

It should be noted that the magnets M and the coils C can also constitute an active damping mechanism to suppress the vibration of the optical system100at a second frequency, wherein the second frequency is less than the first frequency, and the first frequency is greater than 1 Hz.

In some embodiments, the first frequency may be greater than 10 Hz, and the second frequency is less than the first frequency.

As mentioned above, the optical system100not only comprises passive dampers (flexible members W), but also has an active damping mechanism formed by the magnets M and the coils C. Therefore, the vibration of the optical system100at different frequencies can be efficiently suppressed, thus improving safety and stability of the optical system100when used in the vehicle.

FIG.13is a perspective diagram of the two support structures F1and F2connected to each other by a spring R, in accordance with another embodiment of the invention.FIG.14is a cross-sectional view of the two support structures F1and F2connected to each other by the flexible members W and the spring R, in accordance with another embodiment of the invention.

As shown inFIGS.13-14, a spring R is connected between the two support structures F1and F2to increase the shock absorption capability of the optical system100. Moreover, efficient space utilization and miniaturization of the optical system100can also be achieved by the circuit assembly P extending through the spring R (FIG.14). In some embodiments, the optical system100may comprise only the spring R without the flexible members W.

FIG.15is a bottom view of the ball elements B and the clamps50located between the flexible members W.

As shown inFIGS.13-14, four ball elements B and clamps50are respectively disposed on the four sides of the movable part (including the holder20and the frame30). Specifically, each ball element B and each clamp50are located between two of the flexible members W in a horizontal direction (X or Y direction). Moreover, the spring R surrounds the optical axis O, and the four ball elements B are symmetrically arranged around the optical axis O. It should be noted that the ball elements B can be used as universal joints between the holder20and the frame30, thereby improving stability of the optical system100.

In some embodiments, the optical system100may comprise a position sensor (e.g. Hall-effect sensor) disposed on the holder20or the frame30for detecting the displacement of the holder20relative to the frame30.

In some embodiments, the optical system100may comprise a gyroscope (not shown) disposed on the holder20for detecting the motion of the optical module10.

In summary, the invention provides an optical system100that includes at least a passive damper (the flexible member W and/or the spring R) and an active damping mechanism (e.g. the magnets M and the coils C). Therefore, the vibration of the optical system100at high and low frequencies can be both efficiently suppressed, thereby facilitating safety and stability of the optical system100when used in the vehicle.