JPH0748042B2 - Imaging device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image pickup device used in an image analysis device for measuring the arc shape of a discharge lamp.

2. Description of the Related Art Discharge lamps have the advantages of higher efficiency and longer life than halogen bulbs, and because of their compact size, light distribution control is easy, and not only for outdoor lighting but also for indoor lighting, video equipment and automobiles. It has been widely used as a headlight. For these discharge lamps, in order to improve the light utilization efficiency and design an illumination optical system in which the light distribution is controlled, it is necessary to accurately know the shape of the arc tube arc and the emission intensity distribution.

FIG. 5 shows a conventional image pickup apparatus for photographing the shape of the arc of a discharge lamp arc and the emission intensity distribution. In FIG. 5, 1 is an arc, 2 is a discharge lamp, 3 is a power supply circuit for lighting the discharge lamp 2, 4 is an imaging optical system, 5 is an optical density filter, 6 is a camera, and 7 is a measuring unit. The image pickup apparatus includes an image pickup optical system 4, an optical density filter 5, and a camera 6.
It consists of and. In the discharge lamp 2 lit by the current supplied from the power supply circuit 3, the light intensity from the arc 1 is high and exceeds the intensity range that can be photographed by the camera 6 as it is. The light from the arc 1 is attenuated to an appropriate amount and can be photographed by the camera 6 by arranging it as a part of. The measuring unit 7 draws an equal light intensity line for the image data from the camera 6. As an output example of the measuring unit 7 in FIG.
The shape of the arc 1 and the emission intensity distribution of the discharge lamp 2 which is horizontally lit are shown. In FIG. 6, the iso-intensity line is a closed region P _i (i = 1, 2, ..., M) corresponding to each relative emission intensity from the value 1 to the maximum value M. In addition, by displaying in the measuring unit 7 coloring according to the value for each coordinate, it is possible to further clearly show the state of the shape and the emission intensity distribution. Based on such an arc shape and a light emission intensity distribution, a lighting fixture having a high light utilization efficiency has been designed.

However, in the above method, only the arc can be photographed because the emission intensity of the arc is high, and the relative positional relationship of the arc with respect to the electrode of the discharge lamp 2 and the arc tube is unknown. It was In general, the lighting fixture fixes the lamp by supporting the base that connects to the electrodes of the discharge lamp or a part of the arc tube, so even if the shape of the arc and the emission intensity distribution are known, the position of the arc is We could not design a lighting fixture with precise light distribution control because we do not know if it will occur in.

Means for Solving the Problem An imaging optical system, an optical density filter, an illuminating device, a camera, a signal conversion unit, and an image superimposing unit are provided, and the arc in the arc tube when the discharge lamp is turned on is captured by the imaging optical system and the optical system. The image signal captured by the combination of the dynamic density filter and the camera, and the illumination optical device to illuminate the discharge lamp when extinguished so that the shape of the arc tube emerges, and the image pickup optical system, the camera and the image signal are emphasized. An image superimposing unit that superimposes the arc and the image signal captured in the same imaging frame by combining with the signal converting unit is provided.

Action The image of the arc tube when the discharge lamp is turned on and the image when the lamp is off can be superimposed, and the relative position of the arc with respect to the arc tube or the electrode can be known.

Embodiment FIG. 1 shows the structure of an image pickup apparatus according to the present invention. In FIG. 1, 8 is a turret, 9 is an opening, 10 is a control unit, 11 is an image signal switching unit, 12 is an image memory, 13 is a signal conversion unit,
Reference numeral 14 is a signal superimposing unit, 15 is a lighting device, and 16 is a power switch provided between the discharge lamp 2 and the power circuit 3. The imaging device includes a camera 6, a turret 8, a control unit 10, and an image switching unit.
11, an image memory 12, a data conversion unit 13, a signal superposition unit 14, a lighting device 15, and a power switch 16. The turret 8 is circular and has an optical density filter 5 on one semicircle and an opening 9 on the other semicircle so that the other semicircle is a part of the imaging optical system 4. Deploy.
Each part of the image pickup device is controlled by a control signal from the control unit 10. FIG. 2 shows a time chart of control signals from the control unit 10.

The operation of the image pickup apparatus according to the present invention will be described with reference to FIGS. 1 and 2.

First, the image of only arc 1 is recorded. The power switch 16 is closed by a signal from the control unit 10, and the power circuit 3
A current is supplied to the discharge lamp 2 so that the discharge lamp 2 is lit and stable lighting is performed. The turret 8 is rotated by a signal from the control unit 10 and the optical density filter 5 is arranged as a part of the imaging optical system 4. In response to a control signal from the controller 10, the arc 1 is photographed by the camera 6 through the image pickup optical system 4 and the optical density filter 5. The image signal from the camera 6 is input to the image switching unit 11. The image switching unit 11 outputs the image signal to the image memory 12 according to the control signal from the control unit 10. The image memory 12 is controlled by the control signal from the control unit 10.
The image signal from the image switching unit 11 is recorded. Based on the image thus obtained, as shown in FIG. 3 (a), the arc 1
A closed region P _i (i = 1, 2, ..., M) corresponding to each relative light intensity from the value 1 to the maximum value M, which includes only the shape and the emission intensity distribution as information, is obtained.

Next, the shape of the discharge lamp 2 (including the shape of the electrode and the arc tube) is photographed and superposed on the image. The power switch 16 is opened according to a signal from the control unit 10, and the power circuit 3
The supply of the electric current is stopped and the discharge lamp 2 is turned off. The turret 8 is rotated by a signal from the control unit, and the opening 9 is arranged as a part of the imaging optical system 4. The lighting device 15 is driven by a control signal from the control unit 10. The lighting device 15 is
The discharge lamp 1 to be measured is arranged so that the shape of the arc tube is exposed so that the illumination light can be emitted. For example, by irradiating illumination light from a direction of 45 degrees with respect to the optical axis of the imaging optical system 4, the reflected light can capture the shape of the arc tube cross section. The electrodes and the arc tube 2 are photographed by the camera 6 through the imaging optical system 4 according to a control signal from the control unit 10. The image signal from the camera 6 is input to the image switching unit 11. The image switching unit 11 outputs the image signal to the signal conversion unit 13 according to the control signal from the control unit 10. The signal converter 13 converts the image signal according to the signal from the controller 10. FIG. 4 shows an example of signal conversion. FIG. 4 shows an example in which an image signal having a certain value B is output when an image signal having a value A or more is input, and zero when an image signal having a value lower than A is input. Is. The image thus obtained contains only information on the shape of the electrodes and the arc tube in the discharge lamp 2 as shown in FIG. 3 (b). Image memory 12
And the signal conversion unit 13 outputs the image signal recorded in the image memory 12 and the converted image signal to the signal superposition unit 14 based on the control signal from the control unit 10. The signal superimposing unit 14 superimposes the two image signals with their phases being synchronized.

In the image thus obtained, as shown in FIG. 3 (c), the shape of the arc 1 and the emission intensity distribution, the shapes of the electrodes of the discharge lamp 2 and the arc tube, and their relative positional relationships are shown. Is included as information. In FIG. 3 (c), the shape of the arc 1 is the closed area P _i corresponding to the value i of the emission intensity, the shape of the electrode of the discharge lamp 2 and the arc tube is the value B.
The figure Q is composed of points. The positional relationship of the arc 1 in the discharge lamp 2 is P _i and Q in the measuring unit 7.
It can be obtained by measuring the distance from Further, by displaying the color on the color display in accordance with the value for each coordinate in the measuring unit 7, it is possible to further clearly show the shape, the emission intensity distribution, and the relative positional relationship. Since the luminaire fixes the lamp by supporting a base or a part of the arc tube connected to the electrodes of the discharge lamp, by clarifying the position of the arc 1 in the luminaire as described above, the precision of the arc is improved. It is possible to design lighting fixtures with various light distribution controls.

The camera 6 may be a scanning television camera or an imaging camera capable of signal processing for each pixel. The signal superimposing unit 14 may superimpose the input image signals so that the coordinate positions of the images coincide with each other, and the image signals may be analog signals or digital signals.

The control unit 10 may be configured by an electric control device such as a computer or a sequencer, or may be switched by a mechanical device.

Effect of the Invention Since the discharge lamp can superimpose the image of the arc tube when it is turned on and the image when it is off, and the relative position of the arc with respect to the arc tube or the electrode can be known, a lighting fixture with precise light distribution control is designed. it can.

[Brief description of drawings]

FIG. 1 is a block diagram of an image pickup apparatus according to the present invention, and FIG.
FIG. 4 is a time chart of control signals from the control unit, FIG. 3 is a diagram showing an example of an image obtained by the image pickup apparatus of the present invention, and FIG. 4 is a diagram showing an example of signal conversion in the signal conversion unit. FIG. 5 is a block diagram of a conventional image pickup apparatus, and FIG. 6 is a diagram showing an example of an image obtained by the conventional image pickup apparatus. 1 ... Arc, 2 ... Discharge lamp, 3 ... Power supply circuit, 4
...... Imaging optical system, 5 …… Optical density filter, 6 …… Camera, 7 …… Measuring part, 8 …… Turret, 9 …… Aperture, 10
...... Control unit, 11 ...... Image signal switching unit, 12 ...... Image memory, 13 ...... Signal conversion unit, 14 ...... Signal superimposing unit, 15 ...... Illumination device, 16 ...... Power switch

Claims (1)

[Claims] 1. A power switch for opening and closing a power supply circuit for lighting a discharge lamp, an illuminating device for illuminating the electrodes of the lamp and an arc tube, an image pickup optical system, an optical density filter, a camera, a signal converter and an image superimposing unit. The arc lamp in the discharge lamp with the power switch closed, the image signal captured by the combination of the imaging optical system, the optical density filter and the camera with the power switch closed, and the shape of the arc tube are highlighted. Imaging having a signal superimposing unit that superimposes the arc lamp and the image signal captured in the same imaging frame by combining the imaging lamp with the image capturing optical system, the camera, and the signal converting unit of the discharge lamp arc tube illuminated by the lighting device and in the state where the power switch is open. apparatus.