WO2003098915A2

WO2003098915A2 - Camera for cctv having infrared leds

Info

Publication number: WO2003098915A2
Application number: PCT/US2003/015058
Authority: WO
Inventors: Yoonhwa Ko
Original assignee: Components Specialties Inc.
Priority date: 2002-05-15
Filing date: 2003-05-14
Publication date: 2003-11-27
Also published as: WO2003098915A3; KR200285303Y1

Abstract

A camera for CCTV (Closed Circuit Television) having infrared LEDs (Light Emitting Diodes) mounted thereon for capturing clearer images under varying conditions is disclosed. More particularly, the CCTV camera uses a radiating member to absorb the heat generated by the LEDs thereby minimizing the amount of heat transferred to other components. The radiating member by absorbing the heat generated by the LEDs prevents the heat from directly transferring to other components thus reducing the likelihood that the camera will fail due to overheating. The CCTV camera also preferably includes a shielding mechanism thereby preventing the light generated by the LEDs from interfering with the lens thereby diminishing unwanted interference from the LEDs resulting in poor image quality. The CCTV camera may also incorporate a ventilation fan and ventilation path for further cooling down the internal components of the camera thereby further reducing the likelihood that the camera will fail during operation due to overheating.

Description

CAMERA FOR CCTV HAVING INFRARED LEDS

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a camera for CCTV (Closed Circuit

Television) which may be installed in houses, department stores, banks, exhibition halls, etc. to prevent thefts and to generally monitor a particular viewing area. More particularly, the present invention relates to a camera for CCTV having infrared LEDs 1 (Light Emitting Diodes) capable of capturing and transmitting objects clearly even when the brightness of the viewing area falls below a particular level, for example, in dark places or at nighttime. [0002] In general, CCTV cameras have been installed in desired locations for remote monitoring of areas, images, people, etc. CCTV cameras generally include a video sender for sending images, and a display part for receiving and displaying the image signals transmitted by the video sender. The display part may further record the received images if so desired.

[0003] Conventional CCTV cameras are divided into one or two types. Standard

CCTV cameras are typically used at places where a predetermined brightness is continuously maintained during the monitoring period, while infrared Light Emitting Diodes (hereinbelow, referred to as "LEDs") CCTV cameras are typically used at places where the brightness varies according to exterior conditions.

[0004] Research, development and use of CCTV cameras having infrared LEDs has been particularly rapid over the past few years, mainly because of their ability to provide quality images under varying conditions. CCTV cameras having LEDs typically will use a power source to operate an infrared LED when illuminance is less than a predetermined value. The LED will then emit enough infrared light so that the CCTV camera can generate quality images even in dark viewing areas.

[0005] However, a major drawback with CCTV cameras having infrared LEDs is that the use of LEDs produces a lot of heat inside of the cameras, thus greatly increasing the possibility that the internal components will fail due to overheating. Furthermore, the light generated by the LEDs can interfere with the camera's lens thus causing reflection resulting in poor image quality. One solution to this problem was disclosed in Korean Utility Model Publication No. 1994-0001665 (Application No. 1992-0011203) entitled "a closed circuit camera having an infrared lamp mounted thereon." The Korean publication disclosed a CCTV camera having an infrared lamp or infrared LED mounted thereon that used a sensor to determine the illuminance of the viewing area so that the infrared LEDs only operated when the viewing area was below a predetermined illuminance, thus preventing unnecessary energy waste and damage due to high-temperature heat. The CCTV camera also had a ventilation path that helped prevent damage to the internal components of the camera by emitting the heat generated from the infrared lamp or LED to the outside. However, this device suffered from many drawbacks including the fact that the light produced by the LEDs have a tendency to interfere with the camera lens thus causing unwanted reflection. Furthermore, the ventilation path provided an entrance way for water to enter into the camera, thus resulting in the camera breaking due to water leakage. Finally, the CCTV also suffered from its generally large overall size thus making it harder to hide and from the large number of parts necessary to assemble the camera resulting in increased manufacturing costs.

[0006] Another example of a prior art device was disclosed in Korean Utility Model

Registration No. 20-0232668 entitled "a camera for restricting a smog phenomenon of a glass filter."

SUMMARY OF THE INVENTION

[0007] The present invention is directed to a camera for a CCTV (Closed Circuit

Television) having infrared LEDs (Light Emitting Diodes) mounted thereon that substantially overcomes the problems associated with the prior art. [0008] One object of the present invention is to provide a CCTV camera having infrared LEDs mounted thereon, which utilizes a radiating member to absorb heat generated by the infrared LEDs thereby preventing the heat from dissipating to other internal components, thus reducing their likelihood of damage.

[0009] Another object of the present invention is to provide a CCTV camera having infrared LEDs mounted thereon, that further utilizes a ventilation path and a ventilation fan to further cool down the internal components of the camera thereby further reducing the likelihood of damage due to the heat generated by the LEDs. Preferably, the ventilation path is arranged in such a configuration as to prevent rain water from entering. [0010] Another object of the present invention is to provide a CCTV camera having infrared LEDs that further utilizes a sealing ring in close contact with a filter or protective cover to prevent interference between the light generated by the infrared LEDs and the camera lens. Preferably, the sealing ring is maintained in close contact with the filter by a spring or an elastic member. [0011] Another object of the present invention is to provide a CCTV camera having infrared LEDs mounted thereon, which can increase productivity, and reduce manufacturing costs because of its simple structure thus simplifying and reducing the assembling process. [0012] The CCTV camera of the present invention utilizes infrared LEDs to more clearly capture images in dark places, for example, during the nighttime. The CCTV camera generally includes: a housing for enclosing the camera and protecting it from outside elements, a lens part for capturing images, a circuit part for converting and transmitting the images captured, an infrared ray generating part having a number of infrared LEDs mounted thereto, and a radiating member. The radiating member preferably has a central hole for receiving the lens part and a plurality of insertion holes for receiving the infrared LEDs. The primary purpose of the radiating member is to absorb the heat generated by the LEDs, thus reducing the likelihood of heat damage to other components. [0013] The CCTV camera also preferably includes a sealing ring, a filter (i.e., a protective cover), and a spring. The filter is preferably mounted on the front portion of the housing, while the sealing ring is fitted on the circumference of the lens part and has a front end which contacts the filter. The primary purpose of the sealing ring is to act as a shield to prevent light generated by the LEDs from interfering with the lens. Preferably, the spring is mounted in between the lens and the sealing ring to ensure that the front end of the sealing ring is always in contact with the filter even though the lens may vary in position. [0014] Furthermore, the CCTV camera of the present invention may incorporate a ventilation path and ventilation fan for further cooling internal components, thereby further reducing the likelihood of damage.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In the drawings:

[0016] FIG. 1 is an exploded perspective view of a camera for a CCTV having infrared LEDs mounted thereon according to a preferred embodiment of the present invention;

[0017] FIG. 2 is an exploded perspective view of a camera for the CCTV having infrared LEDs mounted thereon according to another embodiment of the present invention;

[0018] FIG. 3 is an exploded perspective view of a camera for the CCTV having infrared LEDs mounted thereon according to a further embodiment of the present invention;

[0019] FIG. 4 is a partially cutaway view of a camera for the CCTV having infrared

LEDs mounted thereon; and

[0020] FIG. 5 is a sectional view taken along the line of A- A of FIG. 4. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0021] For the purpose of promoting an understanding of the principles of the present invention, reference will now be made to an exemplary, non-limiting embodiment of the CCTV camera illustrated in FIG. 1. It is to be understood that this description is exemplary and explanatory and is not to limit the invention which will be defined only by the claims.

[0022] FIG.l is an exploded perspective view of a camera for a CCTV (Closed

Circuit Television) having infrared LEDs (Light Emitting Diodes) mounted thereon according to a preferred embodiment of the present invention. As shown in FIG. 1, the CCTV camera of the present invention generally includes a plurality of infrared LEDs 1, a housing 2, a lens part 3, a circuit part 4, an infrared ray generating part 5, and a radiating member 8.

[0023] Although any housing known in the art may be used and still be within the scope of the present invention, the housing preferably includes front and rear housing members 2, 2' coupled together. The front and rear housing members 2, 2' may be easily uncoupled with one another, thus permitting one to access the internal components of the CCTV camera, which are located within the housing. As shown, preferably the front housing 2 is a cylindrical member having a first and second end. The first end of the front housing preferably has internal threads for engaging the external threads of the rear housing 2'. The second end of the front housing 2 preferably is configured to receive a filter or protective cover 6, preferably made from glass. The front housing 2 and filter 6 may be engaged by any method known in the art, including but not limited to: force-fitting, bonding, threading, etc. Preferably, however, the filter 6 and the front housing 2 are engaged by packing thus forming a liquid tight seal.

[0024] As stated, preferably the rear housing V has external threads for threadedly engaging the front housing 2, although other connection means may be utilized. Furthermore, the rear housing V preferably has a mounting means located thereon for mounting the CCTV camera. Any mounting means known in the art may be used. Preferably, however, the rear housing 2' has a lower portion for engaging an angle controlling member 11, which connects to a fixing bracket 10. The angle controlling member 11 interconnects the rear housing 2' with the fixing bracket 10 such that the rear housing 2', and thus the CCTV camera, is rotatable about the fixing member 10. Any controlling member 11 known in the art may be used. Preferably, however, the controlling member 11 as disclosed in applicant's pending International Application Number PCT/US03/01882 is used. The fixing bracket 10 preferably has holes therethrough for receiving screws, thus permitting the CCTV camera to be mounted wherever desirable. [0025] The CCTV camera also generally includes a lens part 3 for capturing images, a circuit part 4 for converting the images received from the lens part 3 into a signal for transmitting to a display part, and a power source (not shown). The lens part 3 generally includes a lens 31 and a focus control ring 32, the lens 31 preferably being located within the focus control ring 32. The lens 31 maybe any lens known in the art without limitation, preferably however, the lens is one that is able to move back and forth within the focus control ring 32 according to the rotation of the focus control ring 32 thus allowing the camera to capture objects more clearly. The focus control ring 32 preferably is mounted onto an infrared ray generating part 5. The infrared ray generating part 5 preferably has a number of infrared LEDs 1 mounted thereto. Preferably, the infrared LEDs 1 are arranged around the outer circumference of the infrared ray generating part 5 so that the infrared LEDs 1 circumferentially surround the lens part 3, as shown in FIG. 1. [0026] The CCTV camera of the present invention also includes a radiating member

8, the radiating member 8 preferably includes a central hole 81 and a plurality of smaller insertion holes 82, which circumferentially surround the central hole 81. The central hole 81 preferably has a diameter large enough to encircle the focus control ring 32 of the lens part 3. The plurality of smaller insertion holes 82 preferably have a diameter large enough to encircle the infrared LEDs 1. Preferably when assembled the infrared LEDs 1 are inserted into the insertion holes 82, and the lens part 3 is inserted into the central hole 81 such that the infrared ray generating part 5 is in a close relationship with the rear surface of the radiating member 8. More preferably, the infrared ray generating part 5 is fixed to the rear surface of the radiating member 8 by a screw 14, although other means of fixation may be used. Furthermore, preferably, the focus control ring 32 of the lens part 3 is fixed to the radiating member 8 by a set screw 13.

[0027] As a result, the radiating member 8 encircles and isolates the LEDs 1 from one another, and from the rest of the CCTV camera's internal components. Thus, the radiating member 8 permits the light generated from the infrared LEDs 1 to be emitted towards the filter 6 located near the front of the camera, while absorbing the heat generated from the infrared LEDs 1. As a result, the radiating member 8 prevents the light and heat generated from the infrared LEDs 1 to be directly transmitted to the lens part 3, the circuit part 4, etc. Thus the likelihood of damage to the CCTV camera's internal components is diminished by utilizing a radiating member 8 to absorb the heat generated from the infrared LEDs 1, rather than permitting the heat to be transferred to the other components. The radiating member 8 preferably dissipates the heat absorb slowly to the outside through the housing, ventilation path, etc.

[0028] As shown in FIG. 1, the CCTV camera may also incorporate a sealing ring 7.

The sealing ring 7 is designed to act as a shield preventing light, which is produced by the infrared LEDs 1 from interfering with the lens 31. The sealing ring 7 is designed to fit on the circumference of the lens part 3, and has a front end and a rear end. The front end of the sealing ring 7 is designed preferably to contact the filter 6 mounted on the front portion of the housing 2, thus preventing transmission of light, which is produced by the infrared LEDs 1, to be transmitted to the lens 31. Furthermore, to help the front end of the sealing ring 7 remain in contact with the filter 6, the CCTV camera preferably includes a spring 71, which is located in such a manner that one end of the spring 71 is in contact with the radiating member 8, the infrared ray generating part 5, or the lens part 3, etc., while the other end of the spring 71 is in contact with the rear end of the sealing ring 7. The spring 71 by compressing and releasing as the lens 31 moves back and forth within the focus control ring 32 maintains the front end of the sealing ring 7 in contact with the filter 6, thus inhibiting the light produced from the infrared LEDs 1 from interfering with the lens 31. [0029] Alternatively, as shown in FIG. 2, the radiating member 8 may be made in the form of a cone, thus directing the light, which is produced by infrared LEDs, to the front of the camera away from the lens 31, thus preventing the light from interfering with the lens 31 thereby eliminating the need for a sealing ring 7. The cone shaped radiating member 8 further increases absorption of heat by having a larger surface area.

[0030] As shown in FIG. 3, the CCTV camera may further include a ventilation path

23 and a ventilation fan 9. The ventilation path 23 preferably is formed on the rear portion of the housing 2', while the ventilation fan 9 preferably is mounted inside the ventilation path 23 to effectively counteract the heat generated from the infrared LEDs 1. The ventilation path 23 permits air from the outside of the housing to circulate in the housing, thus further helping the radiating member 8 to cool down the internal components of the CCTV camera. The ventilation fan 9 may be incorporated within the camera in order to further help circulate the air in and out of the housing. The use of a ventilation fan 9 is especially useful when an extra wide lens is needed in order to survey a larger area. That is, typically when a larger viewing area is being monitored, the number of LEDs 1 required generally increases, thereby increasing the amount of light and heat produced within the camera, thus increasing the chance of damaging internal components from overheating. To help counteract this additional light and heat, CCTV cameras may further incorporate a ventilation fan 9 and ventilation path 23 as shown in FIGs. 3 and 4. However, it should be noted that a ventilation fan 9 and ventilation path 23 may be used with any embodiment described within the present invention, or, in the alternative may be omitted entirely. [0031] The ventilation path 23 preferably is located in the rear housing 2' and arranged such that the ventilation path 23 has an outer and inner part, as best shown in FIG. 5. The outer part 21 of the ventilation path 23 preferably has a perforation on its bottom portion for admitting air, while the inner part preferably has a perforation on its top portion for admitting air. The alternating open portions permits air to flow into and out of the housing 2 to cool off the internal components of the cameras. The alternating flow paths however keeps moisture and wetness out of the housing 2 thereby reducing the risk of internal components damage due to water.

[0032] As shown in FIG. 4, preferably the ventilation fan 9 is mounted in a spaced apart relationship from the ventilation path 23 so that the air introduced into the housing 2 by the ventilation fan 9 is transmitted to the infrared LEDs 1 and the radiating member 8, and then discharged to the outside by the ventilation fan 9. More preferably the ventilation fan 9 and ventilation path 23 are separated by a space of about 5-lOmm. While the above steps are repeated, vortices and air currents occur in the space between the ventilation fan 9 and the ventilation path 23 as shown in FIG. 5, thereby heat exchange with the outdoor air is freely performed. As a result, the temperature of the camera within the housing 2 is cooled and maintained in a predetermined condition, thereby reducing the potential of damaging the internal components of the camera.

[0033] Finally, the CCTV camera may include an illumination sensor 12, which serves as a switch for supplying/blocking power from the power source to the infrared ray generating part 5.

[0034] Next, the assembling process and the operation of the LED CCTV camera will be described.

[0035] Generally, the infrared LEDs 1, which are mounted on the infrared ray generating part 5, are inserted into the insertion holes 82, and the infrared ray generating part 5 is fixed to the rear surface of the radiating member 8, preferably by a screw 14. Once the infrared LEDs 1 are inserted into the insertion holes 82, the focus control ring 32 of the lens part 3 is fitted into the central hole 81 of the radiating member 8, and the radiating member 8 is fixed to the focus control ring 32, preferably by a screw 13. Next, a wire (not shown) for supplying power to the infrared LEDs 1 is connected to the circuit part 4, and the front housing 2 is coupled with the rear housing 2', while the spring 71 and the sealing ring 7 are fitted on the outside of the lens part 3. When assembly is completed, the assembled camera is installed in a desired location for viewing a specified area. [0036] During monitoring, if the viewing area is bright, for example during the daytime, the illumination sensor 12 does not transmits a signal to the circuit part 4 to supply power to the infrared LEDs 1, thus the infrared ray generating part 5 is in a non-operating condition and the camera simply captures the objects and transmits the images to the display part. However, if the viewing area is dark, for example, at sunset, or in the nighttime, the illumination sensor 12 transmits a signal to the circuit part 4 to supply power to the infrared LEDs 1. Thus, permitting the camera to supply clearer images then would otherwise be possible.

[0037] As previously explained, when a CCTV camera having LEDs 1 is used, the heat generated from the LEDs 1 can cause damage to the other internal components surrounding the LEDs 1, including damaging the lens 31 and circuit part 4. With the present invention however, the heat generated from the infrared LEDs 1 is absorbed by the radiating member 8, and thus the heat generated by the LEDs 1 is not transferred to the other internal components, thus reducing the likelihood of damaging those components. [0038] Furthermore because the CCTV camera preferably includes a sealing ring 7, which preferably is always in contact with the filter 6 because of the elasticity of a spring 71 interposed between the sealing ring 7 and the lens part 3, the light which is emitted from the infrared LEDs 1 does not interfere with the lens 31, thus allowing clear images to be produced by effectively preventing interference between the light generated by the infrared LEDs 1.

[0039] Moreover, as shown in FIG. 3, the CCTV camera may also incorporate a ventilation path 23 and a ventilation fan 9 to more effectively cool the heat generated from the infrared LEDs 1. A ventilation fan 9 and ventilation path 23 is especially recommended when the viewing area requires the use of several LEDs 1, for example, when the viewing area is particularly large. The ventilation fan 9 may be operated simultaneously with the infrared LEDs 1, or the CCTV camera may further incorporate a temperature sensor (not shown), which are widely known in the art, so that the ventilation fan 9 only operates when the temperature is increased beyond a particular temperature.

[0040] The forgoing embodiments are merely exemplary and are not to be construed as limiting the present invention. Many alternatives, modifications, and variations will be apparent to those skilled in the art.

Claims

What is claimed is;

1. A closed circuit television camera having a housing, a lens part for capturing images, a circuit part for converting the images received into at least one video signal, a power source, the lens part and the circuit part being mounted inside the housing, the camera further comprising:

an infrared ray generating part having at least one infrared light emitting diode arranged on the outer peripheral portion of the lens part;

a filter mounted on a front portion of the housing;

a sealing ring fitted on the circumference of the lens part and having a front end being in contact with the filter to prevent transmission of light from the infrared light emitting diodes to the lens part;

a spring mounted at a rear portion of the sealing ring for providing elasticity to bias the front end of the sealing ring to contact the filter during movement of the lens part;

a radiating member having a central hole into which the lens part is inserted and at least one insertion hole into which the at least one infrared light emitting diode is inserted; and

a focus control ring secured to the lens part;

wherein the infrared ray generating part is fixed to the rear surface of the radiating member, and the radiating member is fixed to the focus control ring of the lens part.

2. The camera according to claim 1, wherein the camera comprises a plurality of infrared light emitted diodes; and the radiating member includes a plurality of insertion holes into which the plurality of light emitting diode are inserted.

3. The camera according to claim 2, wherein the plurality of light emitting diodes are arranged around the outer circumference of the infrared ray generating part so that the infrared light emitting diodes circumferentially surround the lens part.

4. The camera according to claim 1 , wherein the radiating member is in the form of a cone.

5. The camera according to claim 1 , wherein the rear housing has a ventilation path formed at the rear portion thereof, which has an outer part perforated at the lower portion and an inner part perforated at the upper portion, and a ventilation fan is mounted inside the ventilation path.

6. A closed circuit television camera having a housing, a filter mounted on the front portion of the housing, a lens part for capturing images, and a circuit part for converting the images received from the lens part into at least one video signal, the camera further comprising:

an infrared ray generating part;

at least one inf ared light emitting diode mounted on the infrared ray generating part;

a radiating member having a central hole into which the lens part is inserted and at least one insertion hole into which the at least one infrared light emitting diode is inserted.

7. The camera according to claim 6, wherein the camera comprises a plurality of infrared light emitted diodes; and the radiating member includes a plurality of insertion holes into which the plurality of light emitting diode are inserted.

8. The camera according to claim 7, wherein the plurality of light emitting diodes are arranged around the outer circumference of the infrared ray generating part so that the infrared light emitting diodes circumferentially surround the lens part.

9. The camera according to claim 6, further comprising a sealing ring, the sealing ring being fitted on the circumference of the lens part and having a front end and rear end, the front end being in contact with the filter.

10. The camera according to claim 9, further comprising a spring, the spring being in contact with the rear end of the sealing ring.

11. The camera according to claim 6, wherein the lens part comprises a lens and a focus control ring.

12. The camera according to claim 11, wherein the infrared ray generating part is fixed to the rear surface of the radiating member and the radiating member is fixed to the focus control ring of the lens part.

13. The camera according to claim 6, wherein the housing comprises a front housing portion and a rear housing portion removeably coupleable with one another.

14. The camera according to claim 6, further comprising a mounting means for fixedly securing the camera and an angle controlling member for rotating the camera about the mounting means.

15. The camera according to claim 6, wherein the lens part comprises a lens and a focus control ring, the lens being located within the focus control ring, and moveable back and forth within the focus control ring.

16. The camera according to claim 6, wherein the radiating member has the form of a cone.

17. The camera according to claim 6, further comprising a ventilation path formed at the rear portion of the housing, the ventilation path having an outer part perforated at the lower portion and an inner part perforated at the upper portion.

18. The camera according to claim 17, further comprising a ventilation fan mounted inside the ventilation path.

19. The camera according to claim 6, further comprising a ventilation fan mounted inside a ventilation path.

20. A video camera comprising:

a housing;

a lens mounted within the housing;

a circuit mounted within the housing for converting the images received from the lens into at least one signal;

at least one infrared light emitting diode mounted within the housing; and

a radiating member having at least one insertion hole into which the at least one infrared light emitting diode is inserted.

21. The camera according to claim 20, wherein the camera comprises a plurality of infrared light emitted diodes; and the radiating member includes a plurality of insertion holes into which the plurality of light emitting diode are inserted.

22. The camera according to claim 21, wherein the plurality of light emitting diodes are arranged around the outer circumference of an infrared ray generating part so that the infrared light emitting diodes surround the lens.

23. The camera according to claim 22, wherein the infrared ray generating part is fixed to the rear surface of the radiating member and the radiating member is fixed to the lens.

24. The camera according to claim 20, further comprising a sealing ring, the sealing ring being positioned between the lens and a filter mounted on the housing.

25. The camera according to claim 24, further comprising a biasing member, the biasing member being positioned between the lens and the sealing ring.

26. The camera according to claim 20, wherein the housing comprises a front housing portion and a rear housing portion removeably coupleable with one another.

27. The camera according to claim 20, ftirther comprising a mounting structure which secures the camera and an angle controlling member for rotating the camera about the mounting structure.

28. The camera according to claim 20, further comprising a focus control ring, wherein the lens is located within the focus control ring, and moveable back and forth within the focus control ring.

29. The camera according to claim 20, wherein the radiating member has the form of a cone.

30. The camera according to claim 20, further comprising a ventilation path formed at the rear portion of the housing, the ventilation path having an outer part perforated at the lower portion and an inner part perforated at the upper portion.

31. The camera according to claim 30, further comprising a ventilation fan mounted inside the ventilation path.

32. The camera according to claim 20, further comprising a ventilation fan mounted inside a ventilation path.