Patent Publication Number: US-2013233341-A1

Title: Image capturing device and vibration dust removal method thereof

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of Taiwan Patent Application No. 101108333, filed on Mar. 12, 2012, in the Taiwan Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an image capturing device and a vibration dust removal method thereof, and more particularly to the image capturing device and the vibration dust removal method capable of adjusting the amplitude of a vibration dust removal operation according to a power level of the image capturing device. 
     2. Description of Related Art 
     Conventional interchangeable-lens digital cameras (such as digital single lens reflex cameras) are generally sold at a price unaffordable to most people. As science and technology advances and the arrival of the digital era, the price of the interchangeable lens cameras drops to an affordable price, so that the interchangeable digital camera becomes a common 3C product for almost everyone. The advantages of the interchangeable lens digital cameras is to provide a camera lens that can be changed appropriately by users to cope with the requirements of taking a scene or a picture. However, most interchangeable lens digital cameras have a movable connecting opening for the installation of the camera lens to the interchangeable lens digital cameras. Foreign substances such as dust and hair may enter into the interchangeable lens digital camera and adhere or attach onto the image sensor during the process of changing the camera lens. As a result, different sized gray spots will appear on the image and affect the quality of the overall image and it will considerable amount of time for users to remove the gray spots by image processing software. 
     At present, most dust removal methods use a vibration dust removal component to perform a vibration dust removal operation of the image sensor, and most interchangeable lens digital cameras do not have a power detection mechanism to perform vibration dust removal operation. If a user performs the vibration dust removal operation without noticing the remaining power condition, the remaining power of the interchangeable lens digital camera will be exhausted after the vibration dust removal operation is performed for some time, so that the interchangeable lens digital camera cannot take a picture as the power is exhausted, and the user may lose the opportunity of recording an important scene. 
     Alternatively, some interchangeable lens digital cameras are preset to perform a vibration dust removal operation during a power-on process, and such vibration dust removal mechanism may cause a failure of taking a picture by the interchangeable lens digital cameras after the vibration dust removal operation of the interchangeable lens digital cameras takes place due to insufficient remaining power, and thus causing tremendous inconvenience to users. 
     Therefore, the inventor of the present invention designs an image capturing device and a vibration dust removal method to overcome the shortcomings of the prior art. 
     SUMMARY OF THE INVENTION 
     In view of the aforementioned problems of the prior art, it is a primary objective of the invention to provide an image capturing device and a vibration dust removal method thereof to overcome the problem of failing capture an image after a conventional vibration dust removal operation takes place. 
     To achieve the foregoing objective, the present invention provides an image capturing device comprising an image sensor, a power supply component, a vibration dust removal component, a power detection module and a controller. The image sensor receives an optical signal and converts the optical signal into an image signal. The vibration dust removal component produces a vibration to perform a dust removal operation of an image sensor. The power detection module detects an electric power value of the power supply component and generates an electric power signal. The controller is electrically coupled to the image sensor, the vibration dust removal component and the power detection module. The controller determines a maximum amplitude of a vibration produced by the vibration dust removal component to control the vibration dust removal component to perform a dust removal operation for the image sensor according to the maximum amplitude of the vibration. 
     Wherein, the controller increases the amplitude of the vibration gradually from low to high, until the amplitude reaches the maximum amplitude, or the controller controls the vibration dust removal component to directly produce the vibration with the maximum value. 
     Wherein, the image capturing device further comprises a detector for detecting whether a replaceable optical component is connected to the image capturing device, if the replaceable optical component is not connected to the image capturing device, the controller determines to drive the image capturing device to perform the vibration dust removal operation. 
     Wherein, the image capturing device further comprises a vibration trigger module, wherein the controller controls the vibration dust removal component to perform the vibration dust removal operation according to a control signal generated by the vibration trigger module when the detector detects the replaceable optical component not being connected. 
     Wherein, the controller controls the vibration dust removal component to stop producing the vibration when the controller controls the vibration dust removal component to produce the vibration for a predetermined time. 
     Wherein, the controller compares the electric power signal with a predetermined power value; if the electric power signal is smaller than the predetermined power value, then the vibration dust removal component is controlled to stop producing the vibration. 
     To achieve the aforementioned objective, the present invention further provides a vibration dust removal method applied in an image capturing device, and the vibration dust removal method comprising the steps of: using a power detection module to detect an electric power value of the image capturing device and generate an electric power signal; and determine a maximum amplitude of a vibration produced by the vibration dust removal component according to the electric power signal, performing a vibration dust removal operation of an image sensor of the image capturing device according to the maximum amplitude. 
     Wherein, the controller increases the amplitude of the vibration gradually from low to high, until the vibration reaches the maximum amplitude, or the controller directly uses the maximum amplitude to control the vibration dust removal component to produce the vibration. 
     Wherein, the method further comprises the steps of using a detector to determine whether a replaceable optical component is connected to the image capturing device; and driving the image capturing device by the controller to perform the vibration dust removal operation if the detector determines that the replaceable optical component is not connected to the image capturing device. 
     Wherein, the method further comprises the following steps: Using a vibration trigger module to output a control signal to the controller if the detector determines that the replaceable optical component is connected to the image capturing device; using the controller drive the vibration dust removal component to perform the vibration dust removal operation according to the control signal. 
     Wherein, the vibration dust removal method further comprises the step of controlling the vibration dust removal component to produce a vibration for a predetermined time, and then controlling the vibration dust removal component to stop producing the vibration. 
     Wherein, the vibration dust removal method further comprises the step of comparing the electric power signal with a predetermined power value; and controlling the vibration dust removal component to stop producing the vibration if the electric power signal is smaller than the predetermined power value. 
     In summation, the image capturing device and the vibration dust removal method thereof in accordance with the present invention have one or more of the following advantages: 
     (1) The image capturing device and the vibration dust removal method of the present invention can detect the electric power value of the power supply component by the power detection module to determine whether or not to perform the vibration dust removal operation, so as to overcome the problem of having insufficient power after performing the vibration dust removal operation. 
     (2) The image capturing device and the vibration dust removal method of the invention can detect the electric power value of the power supply component by the power detection module during the power-on process to determine whether to perform the vibration dust removal operation during the power-on process, so as to reduce the chance of failing to take a picture after performing the vibration dust removal operation during the power-on process. 
     (3) The image capturing device and the vibration dust removal method of the invention can use the controller to determine the maximum value of the amplitude of the vibration produced by the vibration dust removal component according to the electric power signal to perform a vibration dust removal operation, so as to avoiding expending too much power on the vibration dust removal operation. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram of an image capturing device of the present invention; 
         FIG. 2  is a block diagram of an image capturing device in accordance with a preferred embodiment of the present invention; 
         FIG. 3  is a first flow chart of an operation of an image capturing device in accordance with a preferred embodiment of the present invention; 
         FIG. 4  is a second flow chart of an operation of an image capturing device in accordance with a preferred embodiment of the present invention; and 
         FIG. 5  is a flow chart of a vibration dust removal method of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The technical contents and characteristics of the present invention will be apparent with the detailed description of a preferred embodiment accompanied with related drawings as follows. For simplicity, same numerals are used in the following preferred embodiment to represent respective same elements. 
     The image capturing device of the present invention can be an interchangeable-lens camera or a digital single lens reflex camera. To facilitate the description of the technical characteristics of the present invention, the interchangeable-lens camera is used as an example in the following preferred embodiments, but the invention is not limited to the interchangeable-lens camera only. 
     With reference to  FIG. 1  for a block diagram of an image capturing device of the present invention, the image capturing device  2  has a vibration dust removal device  1  comprising: a power supply component  10 , a vibration dust removal component  11 , a power detection module  12  and a controller  13 . Wherein, the power supply component  10  can be a rechargeable or regular battery such as a nickel-cadmium battery, a nickel-hydrogen battery, a zinc-manganese battery, an alkaline manganese battery or a lithium battery. The vibration dust removal component  11  produces a vibration  111  to perform the dust removal operation. The power detection module  12  detects an electric power value  101  of the power supply component  10  and generates an electric power signal  121 . The controller  13  is electrically coupled to the vibration dust removal component  11  and the power detection module  12 , and can be a central processing unit (CPU) or a micro processing unit. The controller  13  determines a maximum amplitude  131  of the vibration produced by the vibration dust removal component  11  according to the electric power signal  121 , so as to control the vibration dust removal component  11  to perform the vibration dust removal operation to an image sensor  20  of the image capturing device  2 . 
     More specifically, when a user turns on the image capturing device or controls the image capturing device to perform the vibration dust removal operation, the power detection module  12  detects the electric power value  101  of the power supply component  10  and generates the electric power signal  121  according to the electric power value  101  and transmits the electric power signal  121  to the controller  13 . The controller  13  compares the electric power signal  121  with a predetermined power value  132 . If the controller  13  determines that the electric power signal  121  is smaller than a predetermined power value  132 , then the vibration dust removal operation will not be performed. On the other hand, if the controller  13  determines that the electric power signal  121  is greater than the predetermined power value  132 , the controller  13  will determine the maximum amplitude  131  of the vibration produced by the vibration dust removal component  11  according to the electric power signal  121 , so as to control the vibration dust removal component  11  to perform the vibration dust removal operation to an image sensor  20 . It is noteworthy to point out that when the controller  13  determines a maximum amplitude  131  of the vibration produced by the vibration dust removal component  11  and controls the vibration dust removal component  11  to increase the amplitude of the vibration from low to high up to the maximum amplitude  131 , or controls the vibration dust removal component  11  to perform the vibration dust removal operation directly by the maximum amplitude  131 . 
     With reference to  FIGS. 2 and 3  for a block diagram of an image capturing device and a first flow chart of an operation of the image capturing device in accordance with a preferred embodiment of the present invention respectively, this preferred embodiment is similar to the previous preferred embodiment, and the similar parts will not be repeated. In the figures, the image capturing device  2  of the present invention can be an interchangeable-lens camera or a digital single lens reflex camera, comprising: an image sensor  20 , a power supply component  10 , a vibration dust removal component  11 , a power detection module  12 , a controller  13 , a detector  14  and a vibration trigger module  15 . The image sensor  20  receives an optical signal  31  from a replaceable optical component  3  and converts the optical signal  31  into an image signal  201 , and the image sensor  20  can be a complementary metal oxide semiconductor (CMOS) or charge coupled device (CCD), an analog/digital circuit, or an image processor. The detector  14  detects whether the replaceable optical component  3  is connected to the image capturing device  2 . The vibration trigger module  15  is electrically coupled to the detector  14 . If the detector  14  detects that the replaceable optical component  3  is not connected, the controller  13  will drive vibration dust removal component  11  to perform the vibration dust removal operation according to a control signal  151  generated by the vibration trigger module  15 . Wherein, the replaceable optical device  3  can be an interchangeable-lens camera such as a digital single lens reflex (DSLR) camera. 
     When a user presses a power button (not shown in the figure) of the image capturing device  2  to turn on the image capturing device  2 , the detector  14  detects whether the replaceable optical component  3  is connected to the image capturing device  2  (as indicated by the step S 301  in  FIG. 3 ). If yes, then the controller  13  will drive the image capturing device  2  to perform a normal operation such as taking a picture, browsing an image or editing an image (as indicated by the step S 302  in  FIG. 3 ). If no, then the detector  14  will continue the detection until the replaceable optical component  3  is connected to the image capturing device  2  (as indicated by the step S 303  in  FIG. 3 ). If the replaceable optical component  3  is connected to the image capturing device  2 , the vibration trigger generating module  15  will generate a control signal  151 , such that the controller  13  decides to drive the image capturing device  2  to perform the vibration dust removal operation according to the control signal  151  (as indicated by the step S 304  in  FIG. 3 ). Now, the power detection module  12  detects an electric power value  101  of the power supply component  10  of the image capturing device  2 , and generates and transmits an electric power signal  121  to the controller  13  (as indicated by the step S 305  in  FIG. 3 ). The controller  13  compares the electric power signal  121  with a predetermined power value  132  (as indicated by the step S 306  in  FIG. 3 ); if the electric power signal  121  is smaller than the predetermined power value  132 , then the controller  13  will control image capturing device  2  to display a warning message on a display unit (not shown in the figure) (as indicated by the step S 307  in  FIG. 3 ); and if the electric power signal  121  is greater than the predetermined power value  132 , the controller  13  will decide to let the image capturing device  2  continue to perform the vibration dust removal operation. If the controller  13  decides to let the image capturing device  2  continue to perform the vibration dust removal operation, the controller  13  will determine a maximum amplitude  131  of the vibration  111  produced by the vibration dust removal component  11  according to the electric power signal  121  (as indicated by the step S 308  in  FIG. 3 ) to control the vibration dust removal component  11  to drive the image sensor  20  to perform the dust removal operation (as indicated by the step S 309  in  FIG. 3 ). When the vibration dust removal component  11  performs the dust removal operation to the image sensor  20 , the controller  13  determines whether or not to produce the vibration  111  for a predetermined time (as indicated by the step S 310  in  FIG. 3 ); if no, then the controller  13  will control the vibration dust removal component  11  to continue performing the dust removal operation to the image sensor  20 . After the controller  13  controls the vibration dust removal component  11  to produce the vibration  111  for a predetermined time, the controller  13  will control the vibration dust removal component  11  to stop producing the vibration  111  (as indicated by the step S 311  in  FIG. 3 ). It is noteworthy to point out that the image capturing device  2  will perform the dust removal operation during a power-on process, and the image capturing device  2  can set the controller  13  to control the vibration dust removal component  11  to increase the amplitude of the vibration gradually from low to high up to a maximum amplitude  131 . Therefore, the vibration dust removal operation can be performed after the replaceable optical component  3  of the image capturing device  2  is replaced in order to avoid performing the dust removal operation at the maximum amplitude  131 , when the dust is adhered on the image sensor  20 . Users can change the setting to the maximum value as needed. However, the invention is not limited to any particular setting. In addition, the detector  14  still continues the detection to detect whether the replaceable optical component  3  is connected to or removed from the image capturing device  2  in a power-on during a normal operation, so as to facilitate performing the vibration dust removal operation. 
     With reference to  FIG. 4  for a second flow chart of an operation of an image capturing device in accordance with a preferred embodiment of the present invention, if a user presses a control button (not shown in the figure) to control the image capturing device  2  to perform the vibration dust removal operation during a normal operation (as indicated by the step S 41  in  FIG. 4 ), the controller  13  will confirm whether there is sufficient power to perform the dust removal operation. Similarly, the controller  13  compares the electric power signal  121  with the predetermined power value  132  (as indicated by the step S 42  in  FIG. 4 ). If there is insufficient power to perform the dust removal operation, then a warning message will be displayed to inform the user (as indicated by the step S 43  in  FIG. 4 ). If there is sufficient power to perform the dust removal operation, then the controller  13  will determine the maximum amplitude  131  of the vibration according to the electric power signal  121  of the power detection module  12  (as indicated by the step S 44  in  FIG. 4 ) and will directly use the maximum amplitude  131  to control the vibration dust removal component  11  to perform the dust removal operation (as indicated by the step S 45  in  FIG. 4 ). Similarly, the users can set or change the vibration dust removal operation as described above. 
     While the vibration dust removal component  11  performs the vibration dust removal operation to image sensor  20 , the power detection module  12  continues detecting the power supply component  10  to generate an electric power signal  121 , and the controller  13  continues comparing the electric power signal  121  with the predetermined power value  132  (as indicated by the step S 46  in  FIG. 4 ) to prevent the situation of failing to take picture due to insufficient power after the vibration dust removal operation takes place and there is no power supply available for charging. In addition, the controller  13  will continue confirming whether the control button is pressed (as indicated by the step S 47  in  FIG. 4 ). If the user no longer presses the control button, the controller  13  will control the vibration dust removal component  11  to stop the vibration dust removal operation (as indicated by the step S 48  in  FIG. 4 ). Wherein, the control button can be one of a plurality of physical press buttons installed on the image capturing device  2 , or a virtual button shown on a touch screen and provided for the user to touch. However, the invention is not limited to any particular type of buttons. It is noteworthy to point out that a restrictive condition can be added between the step S 47  and the step S 48 . The restrictive condition refers to a condition for the controller  13  to control the vibration dust removal component  11  to produce a vibration  111  for a predetermined time, or a condition for the controller  13  to control the vibration dust removal component  11  to stop producing the vibration  111 . In other words, if the vibration dust removal operation has been continued for a certain time and the dust attached onto the image sensor  20  has not been removed, it means that the adhesive force of the dust is strong, so that it is necessary to spend more electric power of the image capturing device  2  to perform the vibration dust removal operation in order to remove the dust. 
     With reference to  FIG. 5  for a flow chart of a vibration dust removal method of the present invention, the vibration dust removal method is applied in an image capturing device which can be an interchangeable-lens image capturing device. The image capturing device comprises an image sensor, a power supply component, a vibration dust removal component, a power detection module and a controller. The vibration dust removal method comprises the following steps: 
     S 51 : Using the power detection module to detect an electric power value of the image capturing device and generate an electric power signal. 
     S 52 : Using the controller to compare the electric power signal with a predetermined power value to determine whether or not to perform a vibration dust removal operation. 
     S 53 : Using the controller to determine a maximum value of the amplitude of the vibration produced by the vibration dust removal component according to the electric power signal to perform a vibration dust removal operation to an image sensor. 
     The details and implementation of a vibration dust removal method of an image capturing device of the present invention have been described in the section of the image capturing device already, and thus will not be repeated. 
     In summation of the description above, the image capturing device and the vibration dust removal method of the present invention can generate an electric power signal provided for the controller to compare when the power detection module starts the vibration dust removal operation or when the power supply component detects the electric power value during the vibration dust removal operation. This method can avoid the situation of failing to take a picture due to insufficient power after the vibration dust removal operation takes place. In addition, the controller determines the maximum value of the amplitude of the vibration produced by the vibration dust removal component according to the electric power signal to execute a vibration dust removal operation, and this method can provide the maximum vibration whenever the power allows to perform the dust removal operation effectively and also prevent expending too much battery power for the vibration dust removal operation.