Background Art For prior arts, there is a method of observing a 360-degree image with first type sector lenses alternately arranged along first and second lines.

However, this conventional method is problematic in that a vertical difference is produced in the process of combining the sector lenses in the first and second lines because the sector lenses are arranged to prevent the overlapping of the sector lenses in the first and second lines.

The construction of a prior art, in which first type sector lenses and second type sector lenses are combined together so as to overcome the above- described problem, is described in detail with reference to accompanying drawings. In the prior art, first type sector lenses are arranged along a reference surface at an angle of 360°, and second type sector lenses are additionally arranged under or over the reference surface to photograph a subject situated under or over the reference surface, respectively. In this case, the sector lenses should be alternately arranged with the first type sector lenses alternating with the second type sector lenses in arrangement (because an observation range is reduced at a

regular rate at its upper or lower portion). Empty spaces are covered by oppositely positioned sector lenses. Fig. 3 is a vertical cross section of a panoramic image photographing apparatus according to an embodiment of the prior art, in which first type sector lenses 1 and second type sector lenses 2 are combined together. In this apparatus, a group of second type sector lenses 2 are arranged along a reference surface, another group of second type sector lenses 2 are arranged under the reference surface to observe an observation range 5 under the reference surface, and a group of first type sector lenses 1 are arranged over the reference surface to observe another observation range over the reference surface, thereby enabling the panoramic image photographing apparatus to observe an observation range of 360°.

However, the prior art panoramic image photographing apparatus is problematic in that the apparatus is complicated and should be precisely fabricated because the apparatus should be constructed with two types of sector lenses fabricated on the basis of different principles and arranged over and under the reference surface, respectively, and it is difficult to install the apparatus because the volume of the apparatus is relatively great. Additionally, a vertical photographing range is limited because it is difficult to add sector lenses under and over existing sector lenses.

Disclosure of the Invention Accordingly, an object of the present invention is to provide a sector lens and method of arranging sector lenses for panoramic photographing, which is capable of not only eliminating a vertical variation that is generated when a convention image photographing apparatus is constructed with only first type sector lenses, but also reducing the volume of an image photographing apparatus, facilitating the fabrication and installation of the image photographing apparatus and allowing a wider vertical photographing range in comparison with the case where two types of sector lenses are combined together.

In order to accomplish the above object, the present invention provides a

360-degree panoramic image photographing apparatus, in which second type sector lenses and third type sector lenses are arranged in a combination manner, or only the third type sector lenses are arranged, so it provides a wider vertical photographing range, has a simple structure, and is easy to fabricate and install.

Brief Description of the Drawings FIG. 1 is a perspective view of a conventional first type sector lens in accordance with an embodiment of the prior art; Fig. 2 is a view showing the use of first type sector lenses for 360-degree panoramic photographing in accordance with an embodiment of the prior art; Fig. 3 is a vertical cross section of a panoramic image photographing apparatus in which first type sector lenses and second type sector lenses are combined together in accordance with an embodiment of the prior art; Fig. 4 is a perspective view of a second type sector lens in accordance with an embodiment of the prior art; Fig. 5 is a view showing the appearance of a third type sector lens in accordance with the present invention; Fig. 6 is a front view of the third type sector lens of the present invention ; Fig. 7 is a vertical cross section of the third type sector lens of the present invention; Fig. 8 is a view showing an arrangement of second type sector lenses for vertical panoramic photographing in accordance with an embodiment of the present invention; Fig. 9 is a vertical cross section of the arrangement of the second type sector lenses for vertical panoramic photographing in accordance with the embodiment of the present invention; Fig. 10 is a view showing a panoramic image shown on the monitors of the second type sector lens for vertical panoramic photographing in accordance with the embodiment of the present invention ; Fig. 11 is a view showing an arrangement of the second type sector lenses

for the panoramic photographing of a lower photographing range in accordance with an embodiment of the present invention; Fig. 12 is a vertical cross section of the arrangement of the third type sector lenses for the 360-degree panoramic photographing of the lower range in accordance with an embodiment of the present invention; Fig. 13 is a view showing a panoramic image shown on the monitors of third type sector lenses in accordance with an embodiment of the present invention; Fig. 14 is a view showing an arrangement in which the second type sector lenses and the third type sector lenses are combined together for the 360-degree panoramic photographing of a reference range and a lower range in accordance with an embodiment of the present invention; Fig. 15 is a vertical cross section showing the arrangement in which the second type sector lenses and the third type sector lenses are combined together for the 360-degree panoramic photographing of a reference range and a lower range in accordance with an embodiment of the present invention; Fig. 16 is a view showing a panoramic image shown on the monitors of the arrangement in which the second type sector lenses and the third type sector lenses are combined together for the 360-degree panoramic photographing of a reference range and a lower range in accordance with an embodiment of the present invention; Fig. 17 is a view showing an arrangement in which sector lenses are arranged at an angle of 360 degrees so that a horizontal reference surface coincides with the upper most image incident line of a third type sector lens arrangement in accordance with another embodiment of the present invention; Fig. 18 is a vertical cross section of the arrangement in which sector lenses are arranged at an angle of 360 degrees so that a horizontal reference surface coincides with the upper most image incident line of the third type sector lens arrangement in accordance with the embodiment of the present invention; Fig. 19 is a view showing a panoramic image shown on the monitors of the arrangement in which the sector lenses are arranged at an angle of 360 degrees

so that a horizontal reference surface coincides with the upper most image incident line of the third type sector lens arrangement in accordance with another embodiment of the present invention; Fig. 20 is a view arrangements in which after the sector lenses are arranged at an angle of 360 degrees so that a horizontal reference surface coincides with the upper most image incident line of the third type sector lens arrangement in accordance with another embodiment of the present invention, other third type sector lenses are additionally arranged under the third type sector lens arrangement in accordance with another embodiment of the present invention; and Fig. 21 is a view showing a panoramic image appearing on the monitors when the sector lenses are arranged at an angle of 360 degrees so that a horizontal reference surface coincides with the upper most image incident line of the third type sector lens arrangement in accordance with another embodiment of the present invention and, thereafter, other third type sector lenses are additionally arranged under the third type sector lens arrangement in accordance with another embodiment of the present invention.

<Description of reference characters of principal elements> 1 : first type sector lens 2: second type sector lens 3: third type sector lens 4: observation range of first type sector lens 5: observation range of second type sector lens 6: observation range of third type sector lens 10 : horizontal reference surface 20: cutout images of third type sector lens 30: image on monitor formed by second type sector lens 40: image on monitor formed by second type sector lens Best Mode for Carrying Out the Invention Hereinafter, there are described a third type sector lens and method of arranging third type sector lenses for panoramic photographing.

A third sector lens situated under a reference surface has a shape that is

downwardly narrowed as shown in Fig. 5 because of a phenomenon in which the developed shape of a sphere is upwardly or downwardly narrowed when the sphere such as a terrestrial globe is developed on a plane. Additionally, when an additional third type sector lens is arranged to observe a wider vertical range, the third type sector lens situated under a reference surface is downwardly narrowed at a regular rate.

For the above-described reason, in the third type sector lens, a first lens is cut out as shown in Fig. 6 with image incident lines taken as reference.

In this case, when the image of a subject reaches the first lens along image incident lines, the light path is slightly bent, thus providing a space in which the first lens and the casing of the third type sector lens are coupled together.

When the light path bent by the cut-out object lens reaches the detecting plate of a Charge-Coupled Device (CCD) sensor through second and third lenses, an image signal of the subject reaches a multi-plate type camera body through a CCD sensor pin, a connector and a cable 20. At this time, the image signal is image processed along with images inputted from other CCD sensors, and the processed image signals are sequentially transmitted to a computer through an image output connector.

In an embodiment, as shown in Fig. 8, a group of second type sector lenses 2 are arranged along a reference surface at regular intervals over an angle of 360° around an incident opening.

Fig. 9 is a vertical cross section of the arrangement of the second type sector lenses 2. A 360-degree panoramic image can be obtained without a phenomenon in which an observation range 5 is divided along a vertical reference surface 10.

Thereafter, a group of third type sector lenses are arranged under the group of second type sector lenses 2 as illustrated in Fig. 11.

Fig. 12 is a vertical cross section of the arrangement of the third type sector lenses arranged under the group of second type sector lenses. In this case, the group of third type sector lenses has a shape that is downwardly narrowed for the reason described above. Accordingly, the cut-out images 20 of the sector

lenses are formed over the photographing range 6 of the group of third type sector lenses.

A panoramic image system is fabricated by arranging the group of second type sector lenses and the group of third type sector lenses as shown in Fig. 14.

Fig. 15 is a vertical cross section of the panoramic image system constructed as described above. An image photographed over the photographing range 5 of the group of second type sector lenses 2 and the photographing range 6 of the group of third type sector lenses 3 is illustrated in Fig. 16.

The construction in which the group of second type sector lenses 2 are employed together with the group of third type sector lenses 3 is suitable for indoor use, but is not suitable for outdoor use in which the panoramic image system is installed at a high outdoor position to observe a wider range.

Hereinafter, there is described a panoramic image system according to another embodiment of the present invention, which is fabricated by combining a group of second type sector lenses and a group of third type sector lenses together.

Referring to Fig. 17, a group of third type sector lenses are arranged over an angel of 360° so that a vertical reference surface coincides with the uppermost image incident line of the group of third type sector lenses.

Fig. 18 is a vertical cross section of the group of third type sector lenses arranged as described above. In accordance with the characteristics of the third type sector lenses as described above, the cut-out images 20 of the group of third type sector lenses 3 appear as shown in Fig. 19.

Fig. 20 is a vertical cross section of construction in which an additional group of third type sector lenses 3 are arranged under the former group of third type sector lenses positioned under the group of second type sector lenses to have a wider vertical observation range. In this case, an image obtained by the combination of only the third type sector lenses 3 appears on a monitor as depicted in Fig. 21.

Industrial Applicability

The sector lens and method of arranging sector lenses for panoramic photographing according to the technical construction of the present invention is capable of panoramically photographing or recognizing a subject in a range of 360° in real time without the use of a mechanical driving unit. Additionally, the sector lens and method provides industrial and manufacturing effects of magnifying a specific portion of a photographed subject by the digital signal processing of an image signal, thus enabling the precise concentrated examination and observation of the subject. Additionally, the sector lens and method does not employ an expensive mechanical driving unit and a driving unit control unit, so the manufacturing and maintenance costs of an apparatus are low and even an unskilled operator can panoramically photograph and recognize a subject in a range of 360°.

In addition, the sector lens and method can observe a subject without a vertical difference, can facilitate the installation of the apparatus and miniaturize and simplify the apparatus because the apparatus can be constructed with only the second type sector lenses and the third type sector lenses, and can replace a conventional system using pan/tilt/zoom lens.