JP2010002502A - Laser pointer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser pointer that can be used for a long period and operated conveniently. <P>SOLUTION: The laser pointer 10 includes an auxiliary power unit 12 and a laser pointer body 14. The auxiliary power unit 12 is connected to a computer. The auxiliary power unit 12 is equipped with a first electric double layer capacitor 16, and charged by using an electric energy supplied from the computer. The laser pointer body 14 is provided with a second electric double layer capacitor 18 and a light emitting part 20, wherein the second electric double layer capacitor 18 is charged using the electric energy charged in the first electric double layer capacitor 16. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention mainly relates to a laser pointer used for presentation.

  A projector is connected to a computer and a presentation is performed using presentation software. A laser pointer is used to point to the material projected on the projector.

  Products that use an electric double layer capacitor as a power source for laser pointers have been announced. The external shape is similar to a USB memory, and charging is performed by making a USB connection to the computer. A lithium ion secondary battery or the like needs a long time for charging, but an electric double layer capacitor can be charged in a short time. For example, an electric double layer capacitor can be used for about 20 minutes after being charged for about 1 minute.

  However, if the electric double layer capacitor runs out during the presentation, the laser pointer needs to be USB charged with a computer. For example, one minute of charging time is required and the presentation is interrupted. This is because the maximum bus power is 5 V and 500 mA when performing USB charging, and the charging time is restricted by this current upper limit value. It cannot be said that it is excellent in terms of usability.

  Increasing the capacity of the electric double layer capacitor eliminates the problem of capacity shortage during the presentation. However, since the shape of the electric double layer capacitor is increased, the shape of the laser pointer is also increased and the usability is deteriorated.

  Patent Document 1 below discloses a laser pointer with a generator. A secondary battery and an electric double layer capacitor are used together. However, the generator is a manual type, and it is unclear how much it can be used with a single charge. According to the description, charging to the electric double layer capacitor takes about 1 minute, but charging of the secondary battery takes about 1 hour, which is not practical.

JP 2000-275574 A

  An object of the present invention is to provide a laser pointer that can be used for a long time and is easy to use.

  The laser pointer of the present invention is connected to a computer, and is charged by the auxiliary power supply unit that charges the first electric double layer capacitor with the electric energy supplied from the computer, and the electric energy charged in the first electric double layer capacitor. And a laser pointer body having a light emitting portion that emits light by the electric energy supplied from the second electric double layer capacitor.

  After charging the first electric double layer capacitor of the auxiliary power supply unit, the second electric double layer capacitor of the laser pointer body is charged. The light emitting unit emits light using electric energy charged in the second electric double layer capacitor.

  The auxiliary power supply unit includes a first charging circuit that charges the first electric double layer capacitor with a constant current, and a first charging circuit that charges the electric energy of the first electric double layer capacitor to the second electric double layer capacitor with a constant current. 2 charging circuit. The laser pointer body does not have a charging circuit.

  The light emitting unit includes a laser diode that emits light using the second electric double layer capacitor as a power source, and a drive circuit for the laser diode.

  The auxiliary power supply unit and the laser pointer main body can be separated. Use only the laser pointer to give instructions during presentations.

  A booster circuit is provided between the second electric double layer capacitor and the light emitting unit to keep the output voltage of the second electric double layer capacitor constant. Since the output voltage of the second electric double layer capacitor decreases as the capacity decreases, the output voltage is made constant by the booster circuit.

  The present invention does not charge the second electric double layer capacitor of the laser pointer body directly from the computer. Charging is performed via the first electric double layer capacitor of the auxiliary power supply unit. Even if the capacity of the second electric double layer capacitor is lost, the laser pointer main body can be used while charging the second electric double layer capacitor by connecting the laser pointer main body and the auxiliary power supply unit. There is no interruption in the presentation as in the past. Further, since the auxiliary power supply unit is provided, the capacity of the second electric double layer capacitor can be reduced, and the usability of the laser pointer body is improved. The combined use of the first electric double layer capacitor and the second electric double layer capacitor can increase the usage time of the laser pointer.

  The present invention will be described with reference to the drawings. The described laser pointer is mainly used in presentations, but is not limited to use in presentations.

  A laser pointer 10 of the present invention shown in FIG. 1 has an auxiliary power supply unit 12 and a laser pointer main body 14. The auxiliary power supply unit 12 and the laser pointer main body 14 are separable. The circuit configuration of the laser pointer 10 is shown in FIG.

  The auxiliary power supply unit 12 is connected to a computer. The laser pointer body 14 is not directly connected to the computer. The auxiliary power supply unit 12 includes a first electric double layer capacitor (EDLC) 16 and is charged using electric energy supplied from a computer.

  The laser pointer body 14 includes a second electric double layer capacitor 18 and a light emitting unit 20. The second electric double layer capacitor 18 is charged using the electric energy charged in the first electric double layer capacitor 16. The light emitting unit 20 emits light using electric energy charged in the second electric double layer capacitor 18.

  After charging the first electric double layer capacitor 16 of the auxiliary power supply unit 12, the second electric double layer capacitor 18 of the laser pointer body 14 is charged. A configuration for this will be described below.

  The auxiliary power supply unit 12 includes a first charging circuit 22 and a second charging circuit 24. The first charging circuit 22 charges the first electric double layer capacitor 16, and the second charging circuit 24 charges the second electric double layer capacitor 18. The first charging circuit 22 and the second charging circuit 24 are circuits that perform constant current charging. This is for improving the charging efficiency of the electric double layer capacitors 16 and 18. An example of a circuit that performs constant current charging is the circuit 26 in FIG.

  An example of the constant current charging circuit 26 shown in FIG. 3A is a step-down chopper type switching converter. In this circuit 26, the choke coil L is connected to the electric double layer capacitors 16, 18, the current flowing through the electric double layer capacitors 16, 18 is detected by the current detector A, and the switching control unit 28 turns on / off the switching element S. Control off. The specific operation is shown by the relationship between the pulse and current shown in FIG. When the switching element S is turned on by a pulse, the current flowing through the electric double layer capacitors 16 and 18 through the choke coil L rises. When the current reaches a predetermined value IH, the pulse is turned off. Thereafter, the current gradually decreases. When the current reaches a predetermined value IL, the pulse is turned on again and the above steps are repeated. Other circuits may be used as long as they can perform constant current charging.

  The constant current charging circuit 26 in FIG. 3 can increase the terminal voltages of the electric double layer capacitors 16 and 18 linearly as shown in FIG.

  The second charging circuit 24 is in the auxiliary power supply unit 12 and not in the laser pointer main body 14. Since the auxiliary power supply unit 12 and the laser pointer main body 14 can be separated, the laser pointer main body 14 is separated from the auxiliary power supply unit 12 to instruct the material displayed on the projector. Since the second charging circuit 24 is not provided in the laser pointer main body 14, the laser pointer main body 16 becomes small and light. The usability of the laser pointer body 16 is improved.

  The auxiliary power supply unit 12 includes a USB terminal 30 for connection with a computer. The first charging circuit 22 charges the first electric double layer capacitor 16 using electric energy from the computer obtained from the power line of the USB terminal 30. Since the computer is used for the presentation, the first electric double layer capacitor 16 can be easily charged by the USB connection.

  Further, the time when the first electric double layer capacitor 16 is charged is affected by the bus power of the USB terminal 30 as described in the prior art. For example, even if it takes 1 minute to charge the first electric double layer capacitor 16, it does not necessarily take the same amount of time to charge the second electric double layer capacitor 18. When the capacity of the second electric double layer capacitor 18 is 10 F and the maximum terminal voltage is 2.5 V, when constant current charging is performed with 1 A from the first electric double layer capacitor 16, Q = CV = It becomes 25 seconds from It. Here, Q is a charge, C is a capacity, V is a voltage, I is a current, and t is time.

  During the presentation, the second electric double layer capacitor 18 is used, and the first electric double layer capacitor 16 is charged from the computer. It is assumed that the capacity of the second electric double layer capacitor 18 has disappeared during the presentation. The laser pointer body 14 and the auxiliary power supply 12 are connected to charge the second electric double layer capacitor 18 from the first electric double layer capacitor 16. In the above example, in the conventional case, charging that took 1 minute is completed in 25 seconds. During this 25 seconds, the use of the laser pointer body 14 is not impossible. Since it is not necessary to directly connect the laser pointer main body 14 to the computer by USB, the laser pointer main body 14 is used while charging the second electric double layer capacitor 18 in a state where the auxiliary power source 12 and the laser pointer main body 14 are connected. be able to. When charging of the second electric double layer capacitor 18 is completed, the auxiliary power supply unit 12 is removed and the auxiliary power supply unit 12 is connected to the computer. Unlike the past, the presentation is not interrupted.

  The light emitting unit 20 of the laser pointer body 14 includes a laser diode 32 and a laser diode drive circuit 34. These use the second electric double layer capacitor 18 as a power source.

  Further, in order to turn on / off the laser diode 32, the push button type switch 36 attached to the housing of the laser pointer 10 and the switch 36 are turned on to energize and turn on the laser diode drive circuit 34. And a switch detection circuit 38 for transmitting. When the ON signal is input from the switch detection circuit 38 to the laser diode driving circuit 34, the laser diode driving circuit 34 causes the laser diode 32 to emit light.

  The output voltage of the second electric double layer capacitor 18 varies depending on the stored capacity. For example, when the capacity decreases, the output voltage also decreases. If the usage time of the laser pointer main body 14 becomes long, the operation of the laser diode 32 and the like cannot be maintained. Therefore, when the output of the second electric double layer capacitor 18 is performed, it is performed via the booster circuit (upconverter) 40. For example, the booster circuit 40 is configured by a semiconductor switch, an inductor, a capacitor, and the like, but is not limited as long as the voltage can be boosted to a constant voltage. As shown in FIG. 4B, even if the output voltage of the second electric double layer capacitor 18 is gradually lowered by using the laser pointer body 14, the voltage can be kept constant by the booster circuit 40. The operation can be kept constant.

  A similar booster circuit 40 is preferably provided between the first electric double layer capacitor 16 and the second charging circuit 24.

  Further, the laser pointer main body 14 includes a voltage detection circuit 42 that measures the terminal voltage of the second electric double layer capacitor 18, a plurality of LEDs 44 having different emission colors, and an LED drive circuit 46 that selects the LEDs 44 that emit light based on the measured terminal voltages. With. The terminal voltage and the capacitance of the second electric double layer capacitor 18 are in a proportional relationship. By measuring the terminal voltage, the capacity of the second electric double layer capacitor 18 can be known. If the LED drive circuit 46 emits different LEDs 44 according to the terminal voltage, the remaining capacity of the second electric double layer capacitor 18 can be known. For example, assume that the emission colors of the three LEDs 44 are red, yellow, and green. During use, the red LED 44 is caused to emit light, and when the terminal voltage is lowered, the yellow LED 44 is caused to emit light. Further, the terminal voltage is gradually increased during charging, and if an increase in the terminal voltage is detected, the green 44 LED is caused to emit light. When charging is completed, a predetermined terminal voltage is obtained. If the terminal voltage is detected, the green LED 44 is turned off.

  A method of using the laser pointer 10 will be described. (1) The auxiliary power supply unit 12 is USB-connected to the computer, and the first electric double layer capacitor 16 is charged. (2) The auxiliary power supply unit 12 and the laser pointer main body 14 are connected, and the second electric double layer capacitor 18 is charged using the first electric double layer capacitor 16 as a power source. (3) When charging of the second electric double layer capacitor 18 is completed, the auxiliary power supply unit 12 and the laser pointer main body 14 are separated, and the laser pointer main body 14 is used to indicate the material displayed on the projector. Meanwhile, the auxiliary power supply unit 12 is connected to the computer via USB and charges the first electric double layer capacitor 16. (4) When the capacity of the second electric double layer capacitor 18 is lost due to the use of the laser pointer main body 14, the auxiliary power source 12 and the laser pointer main body 14 are connected again, and the second electric double layer capacitor 18 is charged. During the presentation, (3) to (4) are repeated.

  As described above, according to the present invention, since the two electric double layer capacitors 16 and 18 are provided, the second electric double layer capacitor 18 serving as the power source of the laser diode 32 is not directly supplied with USB power. By charging the first electric double layer capacitor 16 during the presentation, the second electric double layer capacitor 18 can be charged in a short time. The laser pointer main body 14 can be used even while the second electric double layer capacitor 18 is being charged, and no interruption occurs as in the prior art.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to said embodiment. For example, the auxiliary power supply unit 12 may have the same function as the USB memory. As shown in FIG. 5, the auxiliary power supply unit 12 includes a memory 48 that stores data and software, a memory control unit 50 that stores and reads data in and from the memory 48, and data via the USB terminal 30. And a USB interface control unit 52 for performing input / output.

  During the presentation, the auxiliary power supply unit 12 is connected to the computer via USB, and if data necessary for the presentation is stored in the memory 48 of the auxiliary power supply unit 12, it is not necessary to carry a USB memory separately. In this case, the auxiliary power supply unit 12 cannot be removed from the computer.

  If the same function as that of the USB memory is not necessary, the auxiliary power supply unit 12 and the laser pointer main body 14 may be used for the presentation while being connected. If both the first electric double layer capacitor 16 and the second electric double layer capacitor 18 are fully charged, long-time driving is possible.

  The capacity of the first electric double layer capacitor 16 and the second electric double layer capacitor 18 may be appropriately changed as necessary. If the operating time of the laser pointer 10 is lengthened, the capacity is increased, and if it is reduced in size and improved in usability, the capacity is decreased.

  Similarly to the laser pointer main body 14, the auxiliary power supply unit 12 may be provided with means for knowing the capacity of the first electric double layer capacitor 16. A circuit for measuring the terminal voltage of the first electric double layer capacitor 16, a plurality of LEDs having different emission colors, and a circuit for selecting and emitting LEDs that emit light according to the measured terminal voltages are provided. The capacity of the first electric double layer capacitor 16 can be determined by the color of the light emitting LED, and the usability is improved.

  In addition, the present invention can be carried out in a mode in which various improvements, modifications, and changes are added based on the knowledge of those skilled in the art without departing from the gist thereof.

It is a figure which shows the external appearance of the laser pointer of this invention. It is a figure which shows the circuit structure of the laser pointer of this invention. It is a figure which shows an example of the circuit structure for performing constant current charge, (a) is an example of a constant current circuit, (b) is a figure which shows the relationship between the switching of the circuit of (a), and an output current. . It is a figure which shows the characteristic of charging / discharging of an electric double layer capacitor, (a) shows the characteristic at the time of charge, (b) shows the characteristic at the time of discharge. It is a figure which shows the structure of the USB memory with which an auxiliary power supply part is equipped.

Explanation of symbols

10: Laser pointer 12: Auxiliary power supply unit 14: Laser pointer body 16: First electric double layer capacitor 18: Second electric double layer capacitor 20: Light emitting unit 22: First charging circuit 24: Second charging circuit 26: Constant current Charging circuit 28: switching control unit 30: USB terminal 32: laser diode 34: laser diode drive circuit 36: switch 38: switch detection circuit 40: booster circuit 42: voltage detection circuit 44: LED
46: LED drive circuit 48: Memory 50: Memory control unit 52: USB interface control unit

Claims (6)

An auxiliary power supply connected to the computer and charging the first electric double layer capacitor with the electric energy supplied from the computer;
A laser pointer body having a second electric double layer capacitor that is charged by electric energy charged in the first electric double layer capacitor and a light emitting portion that emits light by electric energy supplied from the second electric double layer capacitor;
With laser pointer. The auxiliary power unit is
A first charging circuit for charging the first electric double layer capacitor with a constant current;
A second charging circuit for charging the electric energy of the first electric double layer capacitor to the second electric double layer capacitor with a constant current;
The laser pointer of claim 1 comprising: The light emitting unit is
A laser diode that emits light using the second electric double layer capacitor as a power source;
A driving circuit for the laser diode;
The laser pointer according to claim 1, further comprising: 4. The laser pointer according to claim 1, wherein the auxiliary power supply unit and the laser pointer main body are separable. The laser pointer according to any one of claims 1 to 4, further comprising a booster circuit that keeps the output voltage of the second electric double layer capacitor constant between the second electric double layer capacitor and the light emitting unit. The auxiliary power unit includes a USB terminal for connection to a computer, and the first charging circuit charges the first electric double layer capacitor using electric energy from the computer obtained from a power line of the USB terminal. Item 10. The laser pointer according to any one of Items 1 to 5.

Images