JPH02103899A - Elongation control device of flash lamp luminous time - Google Patents

Abstract

PURPOSE:To elongate the luminous time of a flash lamp by applying discharged outputs of several supply sections successively to the same flash lamp within a time interval needing no retriggering. CONSTITUTION:At first, when a control signal [a] is generated in the output 7a of a luminous timing control section 7, a trigger generating section 6 is controlled to apply a trigger output to a flash lamp 5, and the control terminal of a gating means 4a is turned on to apply the discharged output of a supply section 2a to the flash lamp 5 through the gating means 4a, so that the lamp 5 can be made luminous. Then after a specified time within a time interval needing no retriggering of the lamp 5, that is at a time immediately before the end of the luminous time, a control signal [b] is generated in the output 7b of the luminous timing control section 7, thereby a gating means 4b is turned on and the discharged output of a supply section 2b is applied to the flash lamp 5 to elongate the luminous time of the lamp 5.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a device for extending and controlling the light emission time of a flash lamp by sequentially applying the discharge outputs of a plurality of power supply units to the same flash lamp. This device is suitable as a flash lamp light emission control device in a reading device.

2. Description of the Related Art Franche lamps used in automobile license plate reading devices generally use high-output xenon lamps, and emit light output from the xenon lamps onto the license plates of moving automobiles. The camera then photographs the reflected light.

Problems to be Solved by the Invention In such cases, if the timing of the light emission is not determined accurately, the camera may not be able to take good pictures.

To solve this problem, it would be possible to extend the light emission time by causing multiple flash lamps to emit light one after another, but this would obviously increase the size and cost of the device.

Therefore, it is necessary to extend the light emission time of the same flash lamp, but in the past there was only a device that could simply adjust the light emission output of a flash lamp, as disclosed in Japanese Utility Model Application No. 61-109099. The present invention aims to provide a device that can extend the light emission time of a flash lamp.

Means for Solving the Problems The present invention provides a plurality of power supply sections, a plurality of unidirectional gate means for connecting each of these power supply sections to the same flash lamp, a trigger generation section for triggering the flash lamp, and a trigger generating section for triggering the flash lamp. comprising a light emission timing control section having an output for controlling the trigger generation section and an output for controlling the gate means,
The light emission timing control section controls the discharge output of one of the power supply sections to be applied to the flash lamp via one of the gate means at a timing when an output for controlling the trigger generation section is generated. , after a predetermined period of time from this timing, the other discharge output of the power supply section is applied to the flash lamp via another of the gate means at a timing during which the flash lamp does not need to be retriggered. A flash lamp light emission time extension control device is provided, which is characterized by having a light emission timing control output for controlling the light emission time.

For production The operation of the device according to the invention is as follows.

First, when the control output of the light emission timing control section is generated, the trigger generation section is controlled to trigger the flash lamp, and the discharge output of one of the power supply sections is transmitted to the flash 67 and the lamp via one of the gate means. is applied, and this flash lamp emits light.

At this time, if - of the gate means is equipped with a control terminal,
The control output of the light emission timing control section is applied to the control terminal at the same timing as the control timing of the trigger generation section. Furthermore, if the - of the gate means is a diode, the control output of the light emission timing control section is not applied to this diode.

Next, after a predetermined period of time from the above-mentioned timing, within a time period in which the flash lamp does not need to be re-triggered, that is, at a timing immediately before the flash lamp is about to finish emitting light, the control output of the light emission timing control section is switched to another of the gate means. The discharge output of the other power source is applied to the flash lamp through this gate means to extend the light emission time of the flash lamp.

Furthermore, if you want to extend the light emitting time, you can further increase the number of power supplies and gate means, and after a predetermined time from the above timing, the light emitting tie 67, -2 mink The gate means may be controlled by the control output of the control section.

In this way, the light emission time of the flash lamp is easily extended in the present invention.

Example Next, embodiments of the present invention will be described with reference to the drawings.

In FIG. 1, known power supply sections 2a to 2d are provided, which are supplied with power from a commercial power source 1 to charge built-in capacitors. Charging control to the above capacitor is performed by the charging control section 3.
This is achieved by the control output of The power supplies 2a-2d are connected to a flash lamp 5, such as a xenon lamp, via unidirectional gate means 48-4d. The gate means 4a to 4d in this example are all unidirectional switch means with control terminals, and so-called SCRs are suitable.

The flash lamp 5 is triggered by a trigger generator 6. The light emission timing control section 7 applies the discharge outputs of the power supply sections 2a to 2d to the flash lamp 5 one after another to generate a control output for extending and controlling the light emission time of the flash lamp 6. Light emission 7... The timing control section 7 has an output cuff d that controls the trigger generation section 6 and an output cuff a to 7 that controls the gate means 4a to 4d.
It is appropriate that the output terminal a is used both for controlling the trigger generating section 6 and for controlling the gate means 4a.

Next, the operation of the above configuration will be explained with reference to FIG. 3 as well.

First, a control signal a is sent to the output cuff a of the light emission timing control section 7.
When this occurs, the trigger generating section 6 is controlled and a fludge occurs.
At the same time, a trigger output is applied to the lamp 5, the control terminal of the gate means 4a is controlled to conduct, and the power supply section 2a
The discharge output is applied to the flash lamp 6 via the gate means 4a, and the flash lamp 5 emits light.

Next, a control signal is generated at the output cuff b of the light emission timing control section 7 at a time when the flash lamp 5 does not need to be retriggered after a predetermined period of time from the above timing, that is, at a timing immediately before the light emission is about to end. As a result, the gate means 4b becomes conductive, and the discharge output of the power supply section 2b is applied to the flash lamp 5, thereby extending the light emission time of the flash lamp 6.

Thereafter, in the same manner, the output cuff C of the light emission timing control section 7,
By successively generating control signals c and d at 7d, the light emission time of the Frangieran Pro is extended, and by setting the timing of the signals generated at the output cuffs a to 7d of the light emission timing control section 7, this implementation is possible. In this example, the light emission time can be approximately four times longer than that of the conventional method.

Next, another embodiment of the present invention will be described with reference to FIG.

In this embodiment, the gate means 4a, which is the unidirectional switch means with a control terminal in the previous embodiment, is replaced with a diode, and the output cuff a of the light emission timing control section is connected to the trigger generation section 6. However, there is no need to connect it to the gate means 4a consisting of this diode.

The operation according to this embodiment is such that the flash lamp 5 is triggered by 9 · -2 through the trigger generation section 6 by the control signal a generated at the output cuff a of the light emission timing control section 7, and the gate is gated by the discharge output of the power supply section 2a. Means 4d
The flash lamp 6 is made to emit light through the
Thereafter, the same operation as in the previous embodiment is performed, and the light emission time of the flash lamp 5 is extended.

Effects of the Invention and More According to the present invention, the discharge outputs of a plurality of power supply units can be applied one after another to the same flash lamp to extend the flash lamp's light emission time. It is suitable for flash lamp emission control devices.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the invention, FIG. 2 is a block diagram showing another embodiment of the invention, and FIG. 3 is a timing diagram showing the operation of the embodiment of the invention. 2d to 2d...Power supply section, 4a to 4d...-
・Gate means, 5...Flash lamp, 6...
Trigger generation section, 7... Light emission timing control section, 7a to 7d... Output of the light emission timing control section. Name of agent: Patent attorney Shigetaka Awano and one other person

Claims (3)

[Claims] (1) a plurality of power supply units, a plurality of unidirectional gate means for connecting each of these power supply units to the same flash lamp, and a trigger generation unit for triggering the flash lamp;
A light emission timing control section has an output for controlling the trigger generation section and an output for controlling the gate means, and the light emission timing control section is configured to control the power supply section at the timing of generating the output for controlling the trigger generation section. The discharge output of one of the gate means is controlled to be applied to the flash lamp through one of the gate means, and after a predetermined time from this timing, the power source is applied to the flash lamp at a timing within which re-triggering is not required. A flash lamp light emission time extension control device, comprising a light emission timing control output for controlling the discharge output of one of the gate means to be applied to the flash lamp through the other of the gate means. (2) The flash lamp emission time extension control device according to claim 1, wherein all gate means are unidirectional switch means with control terminals. (3) The flash according to claim 1, wherein the gate means is a diode that connects one of the power supply parts to the flash lamp, and a unidirectional switch means with a control terminal that connects the other of the power supply parts to the flash lamp. Lamp emission time extension control device.