Abstract:
A dual light sources mouse capable of controlling the on and off state of the second light source is proposed. The dual light sources mouse includes a first sensor unit, a first light emitting unit, a microprocessor unit, a second sensor unit and a second light emitting unit. The dual light sources mouse is an optical mouse with a pair of sensor units. The first sensor unit analyzes the motion state of the mouse by collocating with the first light emitting unit, and then the microprocessor unit controls the on and off state of the second light unit which is collocated with the second sensor unit. The second light unit (for instance: a laser diode) can thus be turned off to ensure the security in use while the dual light sources mouse is in the static state.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to an optical mouse and a light source control method thereof and, more particularly, to a dual light sources mouse capable of controlling the on and off of the second light source and a light source control method thereof. 
         [0003]    2. Description of Related Art 
         [0004]    With continual progress of science and technology, computer mice have evolved from early mechanical type to present optical type. Earlier optical mice must be operated on a special mouse pad having coordinated grids thereon. In more recent optical LED mice, this problem has been improved, but their use is still limited by the material used by the interface for reflecting the light source. If the optical LED mice are used on a reflecting place that will absorb light, transmit light or disturb the reflection of light, they cannot be accurately used for click browsing and operation. 
         [0005]    In order to solve the above drawbacks in the use of optical LED mice and further enhance the resolution, optical laser mice have been proposed. Based on the coherence characteristic of laser light, image of high contrast can be produced to solve the material problem of the reflection surface and also greatly enhance the resolution. 
         [0006]    It should be noted that although light emitting units used by optical mice conform with the safety standard, users still should avoid direct view to ensure the safety, especially for optical laser mice. As shown in  FIG. 1 , an existent optical laser mouse comprises a laser-stream sensor  10   a  and a laser light source  20   a , but has no mechanism for turning off its light source (a laser diode). Therefore, there is safety doubt in the use of conventional optical laser mice. 
       SUMMARY OF THE INVENTION 
       [0007]    An object of the present invention is to provide a dual light sources mouse capable of controlling the on and off state of the second light source. Through the design of dual light sources, the on and off state of the second light emitting unit of the dual light sources mouse can be controlled. 
         [0008]    To achieve the above object, the present invention provides a dual light sources mouse capable of controlling the on and off state of the second light source. The dual light sources mouse comprises a first sensor unit, a first light emitting unit, a second sensor unit, a second light emitting unit and a microprocessor unit. The first light emitting unit is electrically connected to the first sensor unit, and is used to provide a light source of reflected shadow required when the first sensor unit analyzes images. The first sensor unit will output a detection signal to the microprocessor unit. The microprocessor unit then outputs a light source control signal to control a laser driver unit in the second sensor unit for controlling the on and off state of the second light emitting unit according to the detection signal. The first sensor unit is an optical positioning sensor. The first light emitting unit is an LED. The second sensor unit is a laser-stream sensor. The second light emitting unit is a laser diode. 
         [0009]    The present invention also provides a method for controlling the on and off state of the second light source of a dual light sources mouse. The method comprises the steps of: determining whether the mouse has moved according to the analysis of image variation; outputting a static reference signal to the microprocessor unit if the mouse has been determined to have not moved; the microprocessor unit outputting a light source off signal to the laser driver unit according to the static reference signal; turning off the laser driver unit to let the second light emitting unit stop emitting a light source; outputting a motion signal to the microprocessor unit if the mouse has been determined to have moved; the microprocessor unit outputting a light source on signal to the laser driver unit according to the motion signal; and activating the laser driver unit to turn on the second light emitting unit to emit light. 
         [0010]    To achieve the above object, the present invention also provides a dual light sources mouse capable of controlling the on and off state of the second light source. The dual light source comprises a first light emitting unit, a first sensor unit, a second light emitting unit, a second sensor unit and a microprocessor unit. The first sensor unit is electrically connected to the first light emitting unit, and is used to analyze received surface characteristics so as to output a first surface characteristics signal according to the reflected shadow image caused by the first light emitting unit. The second sensor unit is electrically connected to the second light emitting unit, and is used to analyze received surface characteristics so as to output a second surface characteristics signal according to the reflected shadow image caused by the second light emitting unit. The microprocessor is used to receive and compare the first and second surface characteristics signals and output a light source control signal to control the on and off state of a laser driver unit in the second sensor unit. 
         [0011]    The present invention also provides a method for controlling the on and off state of the second light source of a dual light sources mouse. The method comprises the steps of: using a first sensor unit to receive and analyze surface characteristics so as to output a first surface characteristics signal; using a second sensor unit to receive and analyze surface characteristics so as to output a second surface characteristics signal; using a microprocessor unit to receive the first and second surface characteristics signals and determine whether the first and second surface characteristics signals conform to a reference level for turning off the light source; the microprocessor unit outputting a light source off signal to turn off a laser driver unit so as to let a second light emitting unit stop emitting a light source if the answer is yes; and the microprocessor unit outputting a light source on signal to activate the laser driver unit so as to turn on the second light emitting unit to emit light if the answer is no. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawing, in which: 
           [0013]      FIG. 1  is an upward view of a laser optical mouse in the prior art; 
           [0014]      FIG. 2A  is a block diagram of a dual light sources mouse capable of controlling the on and off state of the second light source according to a preferred embodiment of the present invention; 
           [0015]      FIG. 2B  is an upward view of a dual light sources mouse capable of controlling the on and off state of the second light source of the present invention; 
           [0016]      FIG. 3  is a flowchart of a method for controlling the on and off state of the second light source of a dual light sources mouse according to a preferred embodiment of the present invention; and 
           [0017]      FIG. 4  is a flowchart of a method for controlling the on and off state of the second light source of a dual light sources mouse according to another preferred embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0018]    As shown in  FIGS. 2A and 2B , the present invention provides a dual light sources mouse capable of controlling the on and off state of the second light source. The dual light sources mouse comprises a first sensor unit  10 , a first light emitting unit  20 , a microprocessor unit  30 , a second sensor unit  40  and a second light emitting unit  50 . The second sensor unit  40  further comprises a laser driver unit  401 . 
         [0019]    The first sensor unit  10  is an optical positioning sensor, and is used to analyze the variation of image motion to output a detection signal. The detection signal is a motion signal or a static reference signal. The first light emitting unit  20  is an LED, and provides a first light source of reflected shadow required when the first sensor unit analyzes images. The microprocessor unit  30  is used to output a light source control signal according to the detection signal provided by the first sensor unit  10 . If the detection signal is the motion signal, the light source control signal is a light source on signal. Contrarily, if the detection signal is the static reference signal, the light source control signal is a light source off signal. The light source control signal is used to control the on and off state of the laser driver unit  401  in the second sensor unit  40  to turn on or off the second light emitting unit  50 . The laser driver unit  401  can be an electronic circuit. The second light emitting unit  50  is a laser diode for providing a second light source. Moreover, the second sensor unit  40  is a laser-stream sensor that calculates the image motion vector and rate to reflect the motion locus of the mouse cursor (i.e., the operation of the mouse cursor) based on the reflected shadow image of the second light source emitted by the second light emitting unit  50 . 
         [0020]    Therefore, the first sensor unit  10  and the first light emitting unit  20  are always on, and are specially in charge of realtime discrimination of the moving or static state of the mouse to send out the detection signal. The second sensor unit  40  and the second light emitting unit  50  respond to the motion locus of the mouse cursor (i.e., the operation of the mouse cursor). The on and off state of the second light emitting unit  50  is controlled by the light source control signal output by the microprocessor  30 . 
         [0021]    As shown in  FIG. 3 , the present invention provides a method for controlling the on and off state of the second light source of a dual light sources mouse. The method comprises the following steps. First, a first sensor unit  10  is used to analyze the variation of reflected shadow image to determine whether the mouse has moved (Step S 301 ). The first sensor unit  10  is an optical positioning sensor. If the answer is no, the first sensor unit  10  outputs a static reference signal to a microprocessor  30  (Step S 303 ). The microprocessor unit  30  then compares a surface characteristics signal collected by a second sensor unit  40  according to the static reference signal provided by the first sensor unit  10  (Step S 304 ). If the surface characteristics signal is determined to conform to the static reference signal, the microprocessor unit  30  outputs a light source off signal to a laser driver unit  401  in the second sensor unit  40  (Step S 305 ). The laser driver unit  401  then lets a second light emitting unit  50  stop emitting a light source (Step S 307 ). If the answer in Step S 301  is yes, the first sensor unit  10  outputs a motion signal to the microprocessor unit  30  (Step S 309 ). The microprocessor unit  30  then outputs a light source on signal to the laser driver unit  401  according to the motion signal provided by the first sensor unit  10  (Step S 311 ). The laser driver unit  401  is thus activated to turn on the second light emitting unit  50  to emit light (Step S 313 ). If the surface characteristics signal is determined to not conform to the static reference signal in Step S 304 , Step S 311  is jumped to for outputting a laser-on signal. The laser driver unit  401  can be an electronic circuit in the second sensor unit  40 . The second light emitting unit  50  can be a laser diode. 
         [0022]    Besides, in the above description, the first sensor unit  10  and the first light emitting unit  20  are always on, and are only used for realtime discrimination of the moving or static state of the mouse. When the mouse is under operation and the first sensor unit  10  detects image motion, the first sensor unit  10  will provide a motion signal to the microprocessor unit  30 . The microprocessor unit  30  then outputs a light source on signal to activate the laser driver unit  401 , which turns on the second light emitting unit  50  to emit light. At this time, the second sensor unit  40  can accurately calculates the motion vector and rate to ensure normal operation of the mouse cursor. Contrarily, if the mouse is static or the mouse is overturned, the first sensor unit  10  analyzes the variation of image motion and determines it to be static, the first sensor unit  10  will provide a static reference signal to the microprocessor unit  30 . The microprocessor unit  30  then outputs a light source off signal to turn off the laser driver unit  401  so as to let the second light emitting unit  50  stop emitting light, thereby preventing the user from eye damage caused by direct view of the second light emitting unit  50 . 
         [0023]    Reference is made to  FIG. 2A  again. The present invention also provides another preferred embodiment of the dual light sources mouse capable of controlling the on and off state of the second light source. The dual light sources mouse comprises a first sensor unit  10 , a first light emitting unit  20 , a microprocessor unit  30 , a second sensor unit  40  and a second light emitting unit  50 . The second sensor unit  40  further comprises a laser driver unit  401 . The laser driver unit  401  is electrically connected to the second sensor unit  40 , and can be an electronic circuit. The first sensor unit  10  is electrically connected to the first light emitting unit  20 , and is used to analyze surface characteristics received by the first sensor unit  10  so as to output a first surface characteristics signal according to the reflected shadow image of the first light source provided by the first light emitting unit  20 . The second sensor unit  40  is electrically connected to the second light emitting unit  50 , and is used to analyze surface characteristics received by the second sensor unit  40  so as to output a second surface characteristics signal according to the reflected shadow image of the second light source provided by the second light emitting unit  50 . The first sensor unit  10  is an optical positioning sensor, and the second sensor unit  40  is a laser-stream sensor. The first light emitting unit  20  is an LED, and the second light emitting unit  50  is a laser diode. 
         [0024]    The microprocessor unit  30  is used to receive and compare the first and second surface characteristics signals to output a light source control signal for controlling the on and off state of the laser driver unit  401 . Besides, the second sensor unit  40  calculates the image motion vector and rate to reflect the motion locus of the mouse cursor based on the reflected shadow image of the second light source emitted by the second light emitting unit  50 . 
         [0025]    As shown in  FIG. 4 , the present invention provides another preferred embodiment of the method for controlling the on and off state of the second light source of a dual light sources mouse. The method comprises the following steps. First, a first sensor unit  10  is used to receive and analyze surface characteristics so as to output a first surface characteristics signal (Step S 501 ). 
         [0026]    Next, a second sensor unit  40  is used to receive and analyze surface characteristics so as to output a second surface characteristics signal (Step S 503 ). A microprocessor unit  30  is then used to receive the first and second surface characteristics signals and determine whether the first and second surface characteristics signals conform to a reference level for turning off the light source (Step S 505 ). If the answer is yes, the microprocessor unit  30  outputs a light source off signal to turn off a laser driver unit  401  so as to let a second light emitting unit  50  stop emitting a light source (Step S 507 ). If the answer is no, the microprocessor unit  30  outputs a light source on signal to activate the laser driver unit  401  so as to turn on the second light emitting unit  50  to emit light (Step S 509 ). The first sensor unit  10  is an optical positioning sensor, and is always on. The laser driver unit  401  can be an electronic circuit in the second sensor unit  40 , and is used to control the second light emitting unit  50 . The second light emitting unit  50  can be a laser diode. 
         [0027]    Although the present invention has been described with reference to the preferred embodiment thereof, it will be understood that the invention is not limited to the details thereof. Various substitutions and modifications have been suggested in the foregoing description, and other will occur to those of ordinary skill in the art. Therefore, all such substitutions and modifications are intended to be embraced within the scope of the invention as defined in the appended claims.