JPH06281998A - Nighttime photographing device - Google Patents

Abstract

PURPOSE:To photograph an object at a long distance at night by using a laser as a light source irradiating the object in the dark, performing two-dimensional scanning by a laser beam, opening a shutter as soon as the scanning is started, and closing the shutter with the finish of the scanning. CONSTITUTION:The laser beam emitted from a laser oscillator 1 is reflected by a galvano-mirror part 2 controlled in X-axis and Y-axis directions by a mirror control part 3. Since the angle of the galvano-mirror is changed with input voltage, the control part 3 optionally adds voltage inputted in an X-axis control part and a Y-axis control part so as to perform the scanning to an X-Y plane. A synchronizing control part 4 controls the opening/closing of the shutter of a camera 5 by synchronizing with time when the irradiation with the laser beam is performed. Namely, the shutter of the camera 5 is opened at a certain point in the middle of the irradiation with the laser beam and it is closed when the position of the laser beam reaches a next point, thereby realizing the photographing of the laser beam reflected from the object 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a night photographing device,
In particular, the present invention relates to a device for photographing a long-distance subject that cannot be reached by light such as a spotlight at night.

[0002]

2. Description of the Related Art Conventionally, when photographing an object existing in the dark at night, it is necessary to illuminate a bright light or a strobe, or irradiate infrared rays having a wavelength that cannot be seen by human eyes. Therefore, nighttime shooting was performed by using a general camera or an infrared camera. However, it has been impossible to image and monitor an object that exists at a long distance that cannot be reached by light such as stroph using the above-mentioned device.

[0003]

Since a conventional light source such as a spotlight or a strobe is used in the conventional night photographing, the light emitted from the light source is diffused in proportion to the distance and the intensity of the light is attenuated. Will end up. For this reason, there is a problem that it is not possible to photograph a long-distance object that cannot be reached by these light sources.

[0004]

A night-time photographing apparatus of the present invention comprises a galvano mirror unit for scanning a laser beam by combining a mirror that changes according to an input voltage with an X-Y axis, and supplying a current to the galvano mirror unit. XY of the mirror
A mirror control unit that can adjust the shake and angle with respect to the axis, a camera equipped with a telephoto lens that shoots an object irradiated with laser light, and the galvano mirror unit that synchronizes the start and end of laser light scanning. And a synchronization control unit for opening and closing the shutter of the camera.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing a configuration of an embodiment of the present invention,
FIG. 2 is a perspective view of the galvano mirror unit 2 shown in FIG. 1, and FIG. 3 is an axial trace diagram of laser scanning on the subject 7 of the embodiment shown in FIG.

In FIG. 1, 1 is a laser oscillator, 2 is a galvano mirror unit, 3 is a mirror control unit, 4 is a synchronization control unit, 5 is a camera, and 6 is a scan frame setting volume. The laser oscillator 1 generates laser light which is a light source for illuminating a subject. Laser light has very high brightness and coherence and is characterized by a very sharply defined and narrow wavelength.
Therefore, the luminous flux of the laser does not change over a long distance. The galvano mirror unit 2 reflects the laser light and makes X
A device that scans a laser beam in the Y-axis direction.

FIG. 2 shows the structure of the galvano mirror section 2. In FIG. 2, an X-axis controller 12 and a Y-axis controller 13
Thus, the respective mirrors 11 are moved to scan the laser light. The voltage applied to the X-axis controller 12 is arbitrarily set as A → A ′ → A ″ → B (see FIG. 3) in consideration of the performance of the galvanometer mirror and the speed of laser scanning. The more drivable the mirror, the more stable the interval between the horizontal break points, but the slower the horizontal scanning speed.

In FIG. 1, the synchronization control unit 4 controls the opening and closing of the shutter of the camera 5 in synchronism with the time when the laser beam irradiation is present at the points A and D in FIG. That is, the shutter of the camera 5 is opened when the laser light irradiation in FIG. 3 is point A, and the shutter is closed when the position of the laser light reaches point D. The camera 5 in FIG. 1 is equipped with a telephoto lens and is used for photographing a distant object.

The light flux of a laser is generally just a point of light. However, since this point of light has high energy and does not spread over distance, it is used as a signal source for various optical communications, but this device is capable of shooting, monitoring, and monitoring at night using the unique features of this laser. I am trying. In FIG. 1, the laser emitted from the laser oscillator 1 is reflected by the galvano mirror unit 2 controlled in the X-axis direction and the Y-axis direction by the mirror control unit 3. This control unit 3 changes the angle of the galvanomirror with respect to the input voltage, so the X-axis control unit 12
If the voltage input to the Y-axis controller 13 can be arbitrarily applied, the XY plane can be scanned. In FIG. 1, the mirror control unit 3 controls the adjustment of the reflection angle of the mirror by supplying a current to the X-axis control unit 12 and the Y-axis control unit 13 of the galvano mirror.

A concrete description will be given with reference to FIG. When laser scanning is performed on the XY plane, the method shown in FIG.
The scanning starts from the point A and ends at the point D. At that time, a voltage is applied to the Y-axis control unit 13 of the galvanometer mirror so that the irradiation point of the laser light is aligned with the point A. While keeping the voltage applied to the Y-axis controller 13 constant, the X-axis controller 12
The laser light is moved in the horizontal direction by changing the voltage applied to the. Then, when the irradiation point of the laser light moves to the position of point B, the voltage applied to the Y-axis control unit 13 is kept constant while the voltage applied to the X-axis control unit 12 is kept constant. Give the voltage required to move. After that, while keeping the voltage applied to the Y-axis control unit 13 constant again, the voltage applied to the X-axis control unit 12 is varied so that the laser light irradiation point is C point.
The object is moved to a point C ', and an object (subject) existing at a long distance is scanned. At this time, the synchronization control unit 4 connected to the mirror control unit 3 in FIG. 1 causes the shutter of the camera to be opened and closed at the start and end of the scan, and the subject 7
The laser light reflected from is taken.

There are various kinds of laser oscillators 1 such as He-Ne laser, argon laser, and semiconductor laser, but each has a monochromatic spectrum component. Since an inexpensive He-Ne laser is red,
When the subject 7 is scanned by the e-laser and is photographed, it is photographed in red because of red reflected light. For this reason, a white laser is used to capture the color of the subject as it is, but to create a white laser, the R (red), G (green), and B (blue) spectra are used. There is a way to combine three lasers with

In addition, when a moving subject is photographed by laser scanning, if the shutter opening / closing interval of the camera is long, the subject shakes. Therefore, the laser scanning needs to be performed at high speed. The ability to react hypersensitivity is required. Normally, the galvanometer mirror is a pair of X-axis and Y-axis, but the performances for X-axis control and Y-axis control are different. For this reason, when performing a higher speed scan, a more constrained scan becomes possible by substituting the Y-axis mirror for the high-performance X-axis mirror.

[0014]

As described above, the present invention uses a laser as a light source for illuminating an object in darkness,
This light is two-dimensionally scanned at high speed, at the same time, the shutter of the camera is opened at the same time as the start of scanning, and the shutter of the camera is closed at the end of scanning, which has the effect of enabling photographing of a long-distance subject at night.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an exemplary embodiment of the present invention.

FIG. 2 is a perspective view of a galvano mirror unit 2 in FIG.

FIG. 3 is a scanning axis trace diagram of a laser scan of the embodiment shown in FIG.

[Explanation of symbols]

 1 Laser Transmitter 2 Galvano Mirror Section 3 Mirror Control Section 4 Sync Control Section 5 Camera 7 Subject 11 Mirror 12 X Axis Control Section 13 Y Axis Control Section

Claims (1)

[Claims] 1. A mirror that changes in accordance with an input voltage is X-
A galvano-mirror unit that scans combined laser light on the Y-axis, a mirror control unit that supplies a current to the galvano-mirror unit and can adjust shake and angle with respect to the X-Y-axis of the mirror, and laser light irradiation. Night photography, comprising a camera equipped with a telephoto lens for photographing an object, and a synchronization control unit for opening and closing the shutter of the camera in synchronization with the start and end of scanning of the laser beam by the galvano mirror unit. apparatus.