Technical Field The present invention relates to an auto sound book apparatus using a CdS cell, and more particularly to an auto sound book apparatus using a CdS cell, which enables simple manufacture of book pages, reducing the thickness of the pages, and lowering book manufacturing costs by manufacturing a book and an auto sound apparatus separately and installing a CdS cell for detecting turned pages in the auto sound apparatus.

Background Art In general, baby books include pictures and sentences on each page. As babies associate the pictures with the corresponding sentences and parents read the sentences to the babies, they learn speaking and writing. Recently, for the purpose of enhancing learning, auto sound books providing voices recorded with sentences written into each page with background music such that the baby can see the pages and hear as well, have been developed and marketed. Most of these auto sound books comprise a page turn detector attached to a book cover for detecting page turning, a memory for storing voice information corresponding to sentences written in each page, a voice output unit for outputting the voice information stored in the memory, and a controller for reading from the memory the voice information of a page corresponding to a page turn detecting signal provided from the page turn detector and providing the read voice information to the voice output unit. On the other hand, for implementation of the page turn detector of a conventional auto sound book, as configured above, there have been proposed methods for outputting voices through a separate voice apparatus electrically connected to a bar code reader, which is a page recognition tool, for reading a bar code indicated for each page. Methods for printing on each page a detector composed of a plurality of dots and recognizing a corresponding page by touching a handset containing a plurality of photo-sensors to the detector are disclosed in Japanese Utility Model Publication No. Hei2-62464 (May 10, 1990), Korean Utility Model Publication No. 1993- 3334 (February 26, 1993), Korean Utility Model Publication No. 1994-25407 (November 18, 1994), and Korean Utility Model Publication No. 1996-38427 (December 18, 1996). However, these methods have problems in that it is required for a user to intervene in page recognition and it is substantially difficult to operate in considering the user is typically a baby who has not yet learned language skills, which results in ineffective learning. In addition, since the page recognition tool is configured separately from the auto sound book, there arises a problem of the increased costs. To overcome these problems, there have been proposed methods for recognizing pages using a lead switch and a magnet installed at a position corresponding to the lead switch. However, these methods also have problems in that two conductive plates composing the lead switch are not often magnetized and a magnetic force of the magnet installed on each book page may not be precisely recognized. To overcome these problems, there have been proposed methods using a CdS cell. The CdS cell is a device for converting the intensity of light to the intensity of current using a photoconductor whose resistance is lowered when light is incident on a semiconductor surface. Fig. 1 is a perspective view illustrating a state where a CdS cell is inserted into a conventional auto sound book apparatus, Fig. 2 is a cross-sectional view taken along line A-A' in Fig. 1 in a state where a front cover of the auto sound book apparatus shown in Fig. 1 is placed topside, and Fig. 3 is a perspective view illustrating a state where a circuit board is mounted in a back cover in the conventional auto sound book apparatus using the CdS cell. Referring to Figs. 1 to 3, a conventional auto sound book apparatus 10 includes a front cover 10a, a back cover 10b, and a plurality of book pages Pl to Pl 6 provided between the front cover 1 Oa and the back cover 10b. hi the above configuration, the back cover 10b contains a printed circuit board (PCB) on which a CdS cell 35 for power switching, a power supply unit 20, a speaker SP, a connector 40a, and other electronic parts are mounted, for controlling the entire operation of the auto sound book apparatus 10. In addition, on one side of the back cover 10b are formed a plurality of apertures (not shown) to facilitate a voice output from the speaker SP. Each book page Pl to P16 includes various sentences and pictures. In addition, each book page has respective thin-film CdS cells Cl to Cl 6 in such a manner that a first CdS cell Cl is inserted in a first book page Pl, a second CdS cell C2 is inserted in a second book page P2, a third CdS cell C3 is inserted in a third book page P3, ... , and a sixteenth CdS cell C16 is inserted in a sixteenth book page P16. In addition, on one side of each book page Pl to P16, respective apertures 35a are formed at the same position and with the same size. Also, the CdS cell 35 for power switching is mounted in the back cover 10b at a position corresponding to the apertures 35a On the other hand, by taping the top surface of each CdS cell Cl to C 16, malfunction or damage of the CdS cells, which may occur when babies or children touch or detach the CdS cells, can be prevented. In addition, leads drawn out of the plurality of CdS cells Cl to Cl 6 are connected to the printed circuit board mounted in the back cover 10b via the connector 40a Accordingly, when the front cover 10a is opened, light is incident on the CdS cell 35 for power switching, and accordingly, the auto sound book apparatus 10 begins to operate. Thereafter, whenever book pages are turned, the turned book pages are recognized as light is incident on the corresponding CdS cells 40. When a signal indicating the recognition is inputted to a control unit (not shown), the control unit instructs the speaker SP to output voice corresponding to the inputted signal. With the conventional auto sound book apparatus using the CdS cells, the problems related to the malfunction of the apparatus due to an error of page recognition can be overcome. However, since the CdS cells for detecting the turned book pages and signal connection lines are installed inside the book pages, it is difficult to manufacture the book pages. Further, since each book page is so thick that the CdS cell can be contained in the book page, the total thickness of the book becomes too large. Furthermore, since the same number of CdS cells are required as the number of book pages in the book, there is a disadvantage of excessive costs of the book pages.

Disclosure of the Invention Technical Problem The present invention has been made in view of the above problems, and it is an object of the present invention to provide an auto sound book apparatus using CdS cells, which enables simple manufacture of book pages, incurring lower costs for exchange of the book pages, and reducing the total thickness of a book by installing CdS cells for detecting turned book pages at an auto sound apparatus instead of the book pages. Technical Solution In accordance with an aspect of the present invention, the above and other objects can be accomplished by the provision of an auto sound book apparatus using CdS cells, comprising: a bottom cover containing electrical parts and a top cover hinged at the bottom cover, a page turn detecting unit exposed in the proper place of a surface of the bottom cover and including at least two CdS cells for outputting a page turn detecting signal depending on light interception, at least two book pages inserted between the top cover and the bottom cover and containing respective light control units formed in the proper place of the book pages for passing light to all or some of the CdS cells or blocking light from all or some of the CdS cells corresponding to the page order, a voice data storing unit connected to a voice storage means in which voice or sound information corresponding to each page is stored, a voice output unit for receiving and outputting the voice or sound information corresponding to each page, and a control unit for receiving the page turn detecting signal from the page turn detecting unit, reading the voice or sound information from the voice data storing unit to be provided to the voice output unit.

Brief Description of the Drawings The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which: Fig. 1 is a perspective view illustrating a state wherein a CdS cell is inserted into a conventional auto sound book apparatus; Fig. 2 is a cross-sectional view taken along line A-A' in Fig. 1 in a state where a front cover of the auto sound book apparatus shown in Fig. 1 is placed topside; Fig. 3 is a perspective view illustrating a state where a circuit board is mounted in a back cover in the conventional auto sound book apparatus using the CdS cell; Fig. 4 is a perspective view illustrating an auto sound book apparatus using CdS cells according to an embodiment of the present invention; Fig. 5 is a perspective view illustrating a state where a book is placed on an auto sound book apparatus using CdS cells according to an embodiment of the present invention; Fig. 6 is an electrical block diagram illustrating an auto sound book apparatus using CdS cells according to an embodiment of the present invention; and Fig. 7 is a flow chart illustrating a control method of an auto sound book apparatus using CdS cells according to an embodiment of the present invention.

Best Mode for Carrying Out the Invention Hereinafter, an auto sound book apparatus using CdS cells according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. Fig. 4 is a perspective view illustrating an auto sound book apparatus using CdS cells according to an embodiment of the present invention, Fig. 5 is a perspective view illustrating a state where a book is placed on an auto sound book apparatus using CdS cells according to an embodiment of the present invention, and Fig. 6 is an electrical block diagram illustrating an auto sound book apparatus using CdS cells according to an embodiment of the present invention. Referring to Figs. 4 to 6, an auto sound book apparatus 100 using CdS cells comprises a bottom cover 100b containing electrical parts, a top cover 100a hinged 110 at the bottom cover 100b, a page turn detecting unit 120 exposed in the proper place of a surface of the bottom cover 100b and including at least two CdS cells 121a to 121f for outputting a page turn detecting signal of a book 200 depending on light interception, at least two book pages inserted between the top cover 100a and the bottom cover 100b and containing respective light control units 200a formed in the proper place of the book pages for passing light to the CdS cells 121a to 121f or blocking light from the CdS cells 121a to 121 f correspondence to the page order, a voice data storing unit 140 connected to a memory 143 in which voice or sound information corresponding to each page of the book 200 is stored, a voice output unit 150 for receiving and outputting the voice or sound information corresponding to each page, and a control unit 130 for receiving the page turn detecting signal from the page turn detecting unit 120, reading the voice or sound information from the voice data storing unit 140 to be provided to the voice output unit 150. In the above configuration, the page turn detecting unit 120 for detecting turned pages of the book can be implemented by the CdS cells 121a to 121 f, and the voice data storing unit 140 can be implemented by the memory 143 for storing the contents of the book 200, a memory hole 145 into which the memory is inserted, and a memory hole cover 146. A language selection button 162 and a repeat button 164 are connected to the control unit 130 and are provided at desired portions of the surface of the bottom cover 100b. A microphone 168, a user recording button 166 and a user play button 167 are also connected to the control unit 130 and are also provided at desired portions of the surface of the bottom cover 100b. The memory 143, which is composed of a semiconductor integrated circuit (IC), stores voice and sound information in correspondence to each book page. In this case, the memory is divided into a plurality of storing regions by time required for each book page. The voice or sound information is stored in a corresponding storing region allocated by a size required for each book page. For example, a single IC memory which can store voice or sound information for more than one hour by virtue of the rapid development of the semiconductor IC memory techniques is divided into the plurality of storing regions by the time required for each book page, in such a manner that a first page is stored for 2 minutes and 30 seconds, a second page is stored for 3 minutes and 50 seconds, a third page is stored for 5 minutes and 25 seconds, ..., for example. Namely, the memory composed of the single semiconductor IC is divided into the plurality of storing regions such that voice or sound information corresponding to a sentence written on each book page is stored in a corresponding storing region. As needed, the voice or sound information may be stored separately in a first language, a second language, etc. For example, the voice or sound information may be stored separately in a native language, a first foreign language and a second foreign language, hi this case, the user may select a desired one of the native language, first foreign language and second foreign language and hear the voice or sound information in the selected language. The control unit 130 receives the page turn detecting signal from the page turn detecting unit 120, recognizes the turned book pages, reads the voice or sound information corresponding to the recognized book pages from the voice data storing unit 140, and provides the read voice or sound information to the voice output unit 150. In this case, the control unit 130 is preferably implemented by a microprocessor commonly used in the art. The power supply unit 160 may be an independent direct voltage (Vcc) source, such as a 1.5 V battery or a secondary rechargeable cell, which is available from the market, or a direct voltage source obtainable by rectifying a commercial alternating voltage source. The voice output unit 150 receives the voice or sound information from the voice data storing unit 140 under the control of the control unit 130 and outputs the information by voice through a volume adjustment unit (not shown), an amplifying unit (not shown) and the speaker 155. The reference numeral 163, not described, denotes a power switch, and 161 and 165 denote a power indicating LED and a recording/play indicating LED, respectively. Now, a method of confirming the book page turning will be described. When a first page is turned, light is incident on a first CdS cell 121a, which is not hidden by the light control unit 200a. The page turn detecting unit 120 detects this light incidence, informing the control unit 130 of the light incidence. Then, the control unit 130 recognizes the light incidence as "000001" indicating that the first page is turned. Here, "0" indicates an electrical state where light is not detected and "1" indicates an electrical state where light is detected. Similarly, when a second page is turned, light is incident on the first CdS cell 121a and a second CdS cell 121b. Thus, as a signal inputted to the control unit 130 is "000011", it is confirmed that the second page is turned. This confirmation operation is listed below.

Hereinafter, operation of the auto sound book apparatus 100 using the CdS cell according to the embodiment of the present invention will be described in detail. Fig. 7 is a flow chart illustrating a control method of an auto sound book apparatus using CdS cells according to an embodiment of the present invention. It is to be understood that the control unit 130 supervises the entire operation. Referring to Fig. 7, the auto sound book apparatus 100 of the present invention is powered on using a power switch 163 in Step SlO. The control unit 130 determines in Step S 12 whether the plurality of CdS cells 121 detect page turn detecting signals. As a result of the determination in Step S 12, when it is determined that the plurality of CdS cells 121 detect page turn detecting signals, the control unit 130 reads the voice or sound information corresponding to turned pages from the voice data storing unit 140 in Step S 14. In Step S 16, the voice or sound information read from the voice data storing unit 140 is transmitted to the voice output unit 150. At this time, the voice output unit 150 sends the information by voice through the volume adjustment unit (not shown), the amplifying unit (not shown) and the speaker 155. Next, in Step Sl 8, the control unit 130 determines whether there is a response from the plurality of CdS cells 121 over a certain time. As a result of the determination in Step S18, when it is determined that there is no response from the plurality of CdS cells 121 for the certain time, that is, when there is no variation in the state of the page turn detecting signal over a certain time, the voice or sound information read from the voice data storing unit 140 is repeatedly outputted through the speaker 155 by the predetermined number of times in Step S20, and then, the process is then terminated. Accordingly, by preventing a battery from being consumed for a long time when the book pages 200 are unfold, the lifetime of the battery can be prolonged. On the other hand, when it is determined that there is a response from the plurality of CdS cells 121 for the certain time, that is, when there is any variation in a state of the page turn detecting signal for the certain time, the process returns to Step S12 where it is determined whether the plurality of CdS cells 121 detect the page turn detecting signals. On the other hand, the language selection button 162 and repeat button 164, connected to the control unit 130, are provided at desired portions of the surface of the bottom cover 100b. Therefore, when the voice or sound information is stored separately in the first and second languages in the voice data storing unit 140, the user can select a desired one of the first and second languages by operating the language selection button 162, and hear the voice or sound information in the selected language. Also, the user can repeatedly hear the voice or sound information by operating the repeat button 164. Also, if the user operates the user recording button 166 connected to the control unit 130 and provided at a desired portion of the surface of the bottom cover 100b, the user's voice from the microphone 168 is stored in the voice data storing unit 140 under the control of the control unit 130. In addition, the stored voice can be heard by operating the user play button 167. As apparent from the above description, the present invention provides an auto sound book apparatus using CdS cells, which is capable of easily manufacturing book pages, incurring inexpensive costs for exchange of the book pages, and reducing the total thickness of a book by installing CdS cells for detecting turned book pages at an auto sound apparatus instead of the book pages. Further, the CdS cells can be arranged longitudinally at an edge of the bottom cover. Although the auto sound book apparatus using the CdS cells and the control method thereof according to the preferred embodiment of the present invention have been described, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. For example, although the present invention has been applied to auto sound books, it is not limited to this. The auto sound book apparatus of the present invention can be used to notify manuals and cautions of household electric appliances by voice, or is applicable to various fields including wireless terminals, menu cards, digital watches, marketing, etc. hi addition, although a one to one detection method where one CdS cell detects one page turn has been described in the preferred embodiment, a method where 2n page turns can be detected using n CdS cells in order to detect more page turns using fewer CdS cells may be employed.

Industrial Applicability The apparatus enables simple manufacture of book pages, incurring lower costs for exchange of the book pages, and reducing the total thickness of a book. In addition, it is possible to manufacture a more convenient auto sound book apparatus by using the CdS cell for power switching as the power switch. Furthermore, instead of the CdS cells, passive devices such as phototransistors can be used.