KR940011114B1 - Door Horn Imaging Device - Google Patents

Abstract

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Description

Door Horn Imaging Device

1 is a diagram showing a wide side range of an image pickup screen according to the first embodiment of the present invention.

2 is an external view of a door horn camera having an optical filter according to a second embodiment of the present invention.

3 is an external view of the optical filter.

4 is an optical characteristic diagram of the optical filter.

5 is a block diagram of an image capturing unit of the television door horn camera.

6 shows an image captured by the optical filter.

7 is a front view of a conventional TV door horn.

8 is an installation diagram of the TV door horn.

9 is a block diagram of an image capturing unit of the TV door horn.

10 is a view in which a part of the captured screen is in the optical measurement range.

11 is a view in which the entire surface of the captured screen is in the optical measurement range.

* Explanation of symbols for main parts of the drawings

1: TV door horn 2: Monitor body

3: door horn camera 4: video monitor

5: visitor 6: subject

10: camera 11: camera cover

15: door post 16: lens

17 imaging device 18 preamplifier

19: signal processing circuit 20: optical measurement range setting circuit

21: low pass filter 22: detection circuit

23: voltage comparison circuit 24: reference voltage

25 control circuit 26 drive circuit

28: optical measurement part 29: optical filter

30: photosensitive part

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a television door horn, and more particularly, to an image pickup apparatus for a door horn provided with a backlight countermeasure function.

FIG. 7 is a front view of a conventional TV door horn, FIG. 8 is an installation diagram of a door horn camera of the TV door horn, FIG. 9 is a block diagram of an imaging unit of the TV door horn, and FIG. Fig. 11 shows a diagram in which the entire surface of the imaging screen is in the optical measurement range.

In the drawing, reference numeral 1 denotes a television door horn, and the monitor main body 2 installed indoors and the door horn camera 3 provided on the front door and the like are used for wiring. (4) is an image monitor representing the subject 6, such as the visitor (5), (7) is a monitor button to "on", "off" the image monitor 4, (8) is a visitor at home It is a handset that performs a call with (5), and is similar to that used for a telephone. Reference numeral 9 denotes a speaker A provided at the set portion of the handset 8 of the monitor main body 2, 10 a camera for photographing the subject 6, and 11 an upper portion of the camera 10. Camera cover, 12 is a microphone for connecting the visitor 5's voice, 13 is a speaker B for generating the voice of a person at home, 14 is a call button for calling a person at home, 15 ) Denotes a door post, 16 denotes a lens, 17 denotes an image element having an aperture, 18 denotes a preamplifier, 19 denotes a signal processing circuit, 20 denotes an optical measurement range setting circuit, and 21 ) Is a low pass filter, 22 is a detection circuit, 23 is a voltage comparator, 25 is a control circuit, 26 is a drive circuit for opening and closing the aperture, 27 is a synchronization signal generator, and 28 is It's an optical measurement part.

Next, the outline | summary of the operation | movement of a television door horn is demonstrated using FIG. 7 and FIG. 8, First, the door horn camera 3 is attached to the door holder 15 in the imageable height of the visitor 5. FIG. Therefore, when the visitor 5 stands in front of the door horn camera 3 and presses the call button 14, the caller sounds from the speaker A 9 of the monitor main body 2 to notify the person at home. A person at home "turns on" the monitor button 7 so that the visitor 5 picked up by the camera 10 appears on the video monitor 4. Thereafter, the person at home talks to each other by the handset 8 and the visitor 5 by the microphone 12 and the speaker B13.

Here, the imaging of the subject 6 by the door horn camera 3 will be described in detail with reference to FIGS. 9 and 10. Imaging of the subject 6 is projected onto the imaging device 17 through the lens 16. The projected image is photoelectrically converted in the image pickup device 17 and sent out from the preamplifier 18 as an electric image signal. The video signal amplified by the preamplifier 18 is subjected to various video signal processing by the signal processing circuit 19 and output as a video signal. This video signal is used as a feedback signal of the auto iris adjustment mechanism (auto iris mechanism). First, a video signal is sent to the optical measurement range setting circuit 20. In this case, the optical measuring portion 28 is set in the center of the image pickup screen, so that the center portion is optically measured.

Then, the video signal in the optical measuring portion 28 is extracted as the luminance signal, and the high pass noise component is removed by the low pass filter 21. Thereafter, the luminance signal is integrated by the detection circuit 22 and converted into a DC voltage showing an average value. This DC voltage is compared with the reference voltage 24 corresponding to the predetermined aperture value by the voltage comparator 23, and the difference from the reference voltage 24 is sent to the control circuit 25 as a difference signal. The control circuit 25 operates the drive circuit 26 in accordance with this difference signal, adjusts the aperture in the imaging device 17, and makes the brightness of the subject 6 projected on the imaging device 17 optimal.

Incidentally, in the above-described conventional example, the optical measuring portion 28 is set at the center of the image pickup screen and the aperture is adjusted to optimize the brightness of the subject 6, but the optical side range setting circuit 20 is deleted. As shown in FIG. 11, the optical measuring portion 28 is used as the entire image pickup screen, and the video signal of the entire image pickup image is sent to the low pass filter 21 as a luminance signal. The following signal processing is performed as described above. In some cases, the brightness of the captured screen is adjusted.

Since the conventional TV door horn is used to represent the visitor 5 by being installed on the door post 15 or the door of the entrance as described above, the image screen is often a composition of the upper body of the visitor 5.

Therefore, the subject 6, which is the visitor 5, is often arranged in the upper and side portions of the background from the center portion to the lower portion of the captured image. As a result, when the optical measurement portion 28 is set at the center of the image pickup screen for the optical measurement for aperture adjustment, the same composition as the subject 6 occupies most of the central portion to cover the optical measurement portion 28. Otherwise, the aperture adjustment corresponding to the light amount of the subject 6 is not performed, for example, when the subject 6 is positioned below the imaging screen, and the background occupies nearly two thirds of the top of the imaging screen. Aperture adjustment corresponding to the amount of light in the background is executed to cause the subject 6 to be too bright or made. In addition, when the light measuring portion 28 is set to the entire image, strong light such as the sun or an empty space in the background is used. In the case of the existing backlight, the aperture adjustment is performed according to the average value of the light amount of the bright part such as the sun or the empty space and the dark part of the subject 6, so that the subject 6 appears dark. It was.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems, and to provide an image capturing apparatus for a TV door horn capable of capturing an aperture according to the brightness of a subject and imaging without darkening the subject even in a backlight. will be.

An image pickup apparatus for a door horn according to the present invention includes: an image pickup apparatus main body installed near a door to image a door periphery; an image pickup lens provided on the image pickup main body; and optical measuring means for measuring the amount of light in a screen by the image pickup apparatus main body; An aperture driving means for opening and closing the diaphragm of the imaging lens in accordance with the amount of light by the measuring means and an optical measuring range setting means for setting the optical measuring range by the optical measuring means below the imaging screen.

In addition, the door horn imaging apparatus according to the present invention is provided in the vicinity of the door is the image pickup device body for imaging the door surroundings, the image pickup lens provided in the image pickup device body, the optical measuring means for measuring the light amount of the whole image pickup screen by the image pickup device body And an aperture driving means for opening and closing the diaphragm of the imaging lens in accordance with the amount of light by the optical measuring means, and an optical filter provided in the optical path of the imaging lens to reduce the transmittance of at least the upper and both sides of the imaging light region of the imaging screen. It is composed of.

In the door horn imaging apparatus according to the present invention, the lower portion of the screen imaged by the imaging lens is set to the optical measurement range by setting the optical measurement range, and the light amount of the portion is measured using the optical measurement means, Therefore, by operating the aperture driving means, the optical measurement range can be covered with the subject disposed from the center to the lower part of the image pickup screen, and the optical measurement focused on the subject can be performed, and the aperture adjustment is performed according to the amount of light of the subject.

Further, in the mixed-door image pickup device according to the present invention, in the screen image picked up by the image pickup lens, the transmittance of the visible light region at least in the upper part and both sides is reduced by the filter, and the light quantity of the whole image pickup screen is measured by the optical measuring means. By operating the aperture driving means in accordance with the amount of light, the amount of light from the upper and both sides, which tends to become a strong light background when the backlight is generated in the captured image, is reduced, and the amount of light from the center to the bottom remains the same. Optimum aperture adjustment is performed without darkening a subject placed from the center of the captured image downward.

1 is a diagram showing an optical measurement range of an image pickup screen according to the first embodiment of the present invention. And since the imaging part block diagram of a television door horn is the same as that of a conventional example, FIG. 9 is useful.

In the drawings, descriptions of (4) to (6) and (16) to (27) are the same or corresponding parts as in the prior art, and thus description thereof is omitted. The optical measurement portion 28 is set by the optical measurement range setting circuit 20 to set the vertical direction to about 33% below the entire photographic screen dimension and the horizontal direction to about 70% of the center portion. Here, the main body of the imaging device is a door horn camera 3, the imaging lens is a lens 16, the optical measuring means is an imaging device 17, the aperture driving means is a driving circuit 26, and the optical measuring range setting means is optical measurement. Corresponds to the range setting circuit 20, respectively.

Next, the operation will be described.

First, in the imaging image of the subject 6 such as the visitor 5 by the door horn camera 3, the operation of each block other than the optical measurement range setting circuit 20 is the same as the conventional example, and thus description thereof is omitted. Next, optical measurement of the captured image by the optical measurement range setting circuit 20 will be described.

The optical measurement range setting circuit 20 sets the optical measurement range below the image pickup screen as shown in FIG.

For this reason, during the imaging of the visitor 5, the probability of measuring strong light such as the sun or the empty space which tends to exist on the top or both sides of the imaging screen is lowered, and the part of the body having a larger area than the face of the visitor 5 is obtained. This is to be measured optically. Therefore, the ratio other than the visitor 5 occupied in this optical measurement range becomes small, the optical measurement based on the visitor 5 is performed, and an aperture is adjusted. In the case of the imaging for the monitor near the entrance, the probability of imaging a background or a building is higher than that of the empty space or the sun in the optical measurement range, and optically measures the object existing on the ground, and performs aperture adjustment accordingly.

In addition, the diaphragm adjustment by this optical measuring method is mainly employ | adopted as the advanced type of the TV door horn 1 in many cases.

2 is an external view of a door horn camera having an optical filter according to a second embodiment of the present invention, FIG. 3 is an external view of the optical filter, FIG. 4 is an optical characteristic view of the optical filter, and FIG. 6 is a block diagram showing an image captured by the optical filter.

In the drawings, descriptions of (3) to (5), (10) to (14), and (16) to (28) are the same or corresponding parts as in the prior art, and thus description thereof is omitted. Reference numeral 29 denotes a cellophane-shaped optical filter having the characteristics shown in FIG. 4 and reducing the transmittance of the light guide region. In addition, the main body of the imaging device 3 is a door horn camera 3, the imaging lens is a lens 16, the optical measuring means is an image sensor 17, the aperture driving means is a driving circuit 26, the optical measuring range setting means is set the optical measuring range Corresponds to the circuit 20, respectively. Numeral 30 denotes a photosensitive portion on the picked-up screen by the optical filter 29.

Next, the operation will be described.

First, in the imaging of the subject 6 such as the visitor 5 by the door horn camera 3, the operation of each block other than the optical filter 29 is the same as in the conventional example, and thus description thereof is omitted. Light quantity reduction of the picked-up screen by (29) will be described.

The optical filter 29 is attached to the inner part of the camera cover 11 positioned above the camera 10 as shown in FIG. 2, and in the image pickup screen, as shown in FIG. Reduce the amount of light on both sides. For this reason, during the imaging of the visitor 5, the amount of light in the background portion is reduced by the optical filter 29 to become the photosensitive portion 30 even in a backlit state in which strong light such as the sun or an empty space exists in the background. Aperture adjustment is performed in accordance with the amount of light in the entire captured image. Therefore, even in the backlight, the visitor 5 can be clearly displayed without darkening the visitor 5. In addition, even in the case of imaging for the monitor of the front door, strong light such as the sun or the empty space, which tends to exist in the background of the imaging screen, can be reduced, making the imaging screen easier to see.

And the photosensitive method by this optical filter 29 is mainly employ | adopted as the popular type of the TV door horn 1.

Incidentally, in the above embodiment, the optical filter 29 is provided above the camera 10, but the lens 16 may be provided between the imaging elements 17.

As described above, according to the present invention, the lower part of the image pickup screen is set as the optical measuring range by the optical measuring range setting means, the light quantity of the range is measured by the optical measuring means, and the aperture is opened and closed by the aperture driving means according to the value. Since the aperture adjustment is mainly performed on the subject placed below the image pickup screen, the aperture can be clearly displayed without darkening the visitor, which is the subject even in backlight, and the background is used even when the landscape is the subject. The image can be displayed without being influenced by strong light such as the sun or the empty space, so that the captured image can be easily seen at all times.

Further, according to the present invention, the amount of light on the upper side and both sides of the background portion of the captured image is reduced by the filter, and then the whole of the image generated by the optical measuring means is optically measured, and accordingly the aperture driving means Since the aperture is configured to be closed again, it is possible to make the captured image easier to see by performing the aperture adjustment according to the amount of light of the subject in the center without being affected by the background even during backlighting, and at the same time, to perform a cheap and simple backlighting measure. It can be effective.

Claims (2)

An imaging device body (3) installed near the door to capture an image of the periphery of the door, an imaging lens (16) provided on the imaging device body, and optical measuring means (17) for measuring the amount of light in an image captured by the imaging device body; Aperture driving means 26 for opening and closing the diaphragm of the imaging lens according to the amount of light by the optical measuring means and optical measuring range setting means 20 for setting the optical measuring range by the optical measuring means below the image pickup screen. Door horn imaging device comprising a. An imaging device body (3) installed near the door to capture an image around the door, an imaging lens (16) provided on the imaging device body, and optical measuring means (17) for measuring the amount of light of the entire imaging screen by the imaging device body; An aperture driving means 26 for opening and closing the aperture of the imaging lens and an optical path of the imaging lens to reduce the transmittance of at least an upper portion of the imaging screen and a visible light region on both sides of the imaging screen according to the amount of light by the optical measuring means; A door horn imaging device comprising a filter (29).