referring to fig3 there is shown a portable optical disc apparatus according to an embodiment of the present invention that includes an optical pickup 13 secured onto an case 16 . the optical pickup 13 is secured onto the case 16 to search an optical disc 11 in the fine search mode , thereby recording or reproducing data . in other words , the optical pickup 13 accesses only an area within a specific radius range where the fine search is available in a recordable / reproducible area existing in the optical disc 11 . a spindle motor 12 is secured onto the case 16 like the optical pickup 13 to rotate the optical disc 11 at a constant speed . since the optical pickup 13 is in a secured state , the optical pickup transfer devices such as the optical pickup carriage motor 4 and the guide shaft 4 a , etc . of conventional devices are not needed and are not present . accordingly , the present portable optical disc apparatus assures an extra space corresponding to a space occupied by the optical pickup transfer devices and the sled base 5 , so that it can be made into a slim - type apparatus as seen from the drawing . for the sake of making a servo control , as shown in fig4 the present portable optical disc apparatus includes a signal processor 17 connected to an output line of the optical pickup 13 , a servo driver 18 for driving an actuator 13 b of the optical pickup 13 , and a controller 19 for controlling the signal processor 17 and the servo driver 18 . the signal processor 17 detects a radio frequency signal and servo error signals , such as focusing and tracking error signals , etc ., from an output signal of the optical pickup 13 . the servo driver 18 drives the actuator 13 b attached with an objective lens 13 a of the optical pickup 13 in accordance with the servo error signals detected from the signal processor 17 . in other words , when a track error signal or a focusing error signal is detected from the signal processor 17 , the servo driver 18 drives the actuator 13 b in a horizontal or vertical axis direction in accordance with the error range . as a result , the optical pickup 13 can stably record or reproduce data in the fine search mode or other modes . an optical disc 11 according to an embodiment of the present invention is accessed changeably in both an optical disc apparatus of conventional fixed - type information equipment such as a personal computer and the portable optical disc apparatus as shown in fig3 . in other words , the entire recordable / reproducible area of the optical disc 11 can be accessed by the optical disc apparatus of the conventional fixed - type information equipment , whereas only an area within a specific radius range is accessed by the portable optical disc apparatus as shown in fig3 according to the present invention . to this end , the optical disc 11 has a different position in a lead - in area in accordance with an area accessible by the portable optical disc apparatus as shown in fig3 . fig5 and fig6 are plan views depicting optical discs according to embodiments of the present invention . referring to fig5 the present optical disc 11 includes a lead - in area arranged at the innermost circumference thereof , and a data area arranged between the lead - in area and the outermost circumference thereof . a disc management information such as a position information , etc . is written into the lead - in area . by referring to this management information , the optical disc apparatus of the present invention accesses a desired position on the optical disc 11 to record or reproduce data on or from the corresponding position . the data area is divided into a first data area adjacent to the lead - in area and a second data area arranged between the first data area and the outermost circumference end of the optical disc 11 . the entire data area including the first and second data areas is accessible by the optical disc apparatus installed at the conventional fixed - type information equipment . the first data area also is accessible by the optical disc apparatus of fig3 recording and reproducing data only in the fine search mode . in other words , the portable optical disc apparatus accesses only the first data area that can be retrieved in the fine search mode according to one embodiment of the present invention . alternatively , the present optical disc apparatus may access only the second data area rather than the first data area . in this case , since the lead - in area referred by the optical disc apparatus exists in a distant position beyond an accessible search range , an access to the second data area may not be realized . to this end , the present optical disc 11 may have a lead - in area arranged in such a manner to co - exist between the innermost circumference and the outermost circumference thereof as shown in fig6 according to another embodiment of the present invention . an identification code indicating a start of the corresponding area can be inserted in the vicinity of the start position of the second data area . if the second lead - in area is arranged at the outermost circumference of the disc as shown in fig6 then the present optical disc apparatus can refer to the second lead - in area to read out the management information when it accesses the second data area . herein , a management information required for accessing only the second data area can be written into the second lead - in area . otherwise , all the management information required for accessing the entire data area including the first and second data areas may be written into the second lead - in area similar to the first lead - in area . a data capacity stored in an area within a specific radius range of the optical disc 11 accessible by the present portable optical disc apparatus can be calculated as described below . referring to fig7 it is assumed that the optical disc 11 is an improved msr - cad ( magnetic super resolution - center aperture detection ) disc which is one of a magneto - optical disc , and that a radius r thereof is 25 mm and a width x at a specific radius range zone thereof is 4 mm . an area a of the specific radius range zone x is determined by the following equation : from the equation ( 1 ), when r and x are replaced by 25 mm and 4 mm , respectively , the area a of x becomes 579 mm 2 ( 0 . 89 in 2 ). since a maximum recording capacity of the improved msr - cad disc is 9 gbit / in 2 , a maximum recording capacity that can be stored in the specific radius range zone x reaches 1 . 0 gbits ( 0 . 89 in 2 × 9 gbits / in 2 ). accordingly , a video data corresponding to more than 30 minutes can recorded within the specific radius range zone although it depends upon a resolution . as described above , according to the present invention , the optical pickup is secured onto the case to access the optical disc , thereby eliminating the need for the optical pickup transfer devices and the sled base . accordingly , a vibration of the optical pickup transfer devices and the sled base themselves or an external interference and a vibration transferred from the exterior into the optical pickup by means of the optical pickup transfer devices and the sled base is minimized , a stable recording and reproduction can be not only made , but also the optical disc apparatus can be made into a slim - type apparatus to such an extent that the optical pickup transfer devices and the sled base are eliminated from the optical disc apparatus . in addition , the portable optical disc apparatus has a management information area ( i . e ., lead - in area ) for a data area within a limited specific radius range arranged in the vicinity of the data area within the specific radius range , so that it is adaptive for an optical disc apparatus accessing only the data area within the specific radius range . although the present invention has been explained by the embodiments shown in the drawings described above , it should be understood to the ordinary skilled person in the art that the invention is not limited to the embodiments , but rather than that various changes or modifications thereof are possible without departing from the spirit of the invention . accordingly , the scope of the invention shall be determined only by the appended claims and their equivalents .