JPH02288559A - Camera incorporated video tape recorder - Google Patents

Abstract

PURPOSE:To avoid the waste of recording in error a video image with flicker in existence by allowing a system control means to apply optimum shutter speed automatically receiving a flicker detection signal and simultaneously managing the timing of video recording start, as well. CONSTITUTION:A flicker detection means 12 is provided, which detects flicker and outputs a flicker detection command 15. Moreover, a system control means 13 is provided, which decoding a flicker detection command 19, outputs a shutter speed switching command 16 and controls the video recording start so that it is surely implemented after the prescribed shutter speed is selected. Furthermore, a shutter speed changeover means 14 is provided, which sets the shutter speed to the speed in which no flicker takes place by using the shutter speed switching command 16. Thus, the user of the camera incorporated VTR uses the camera without caring about flicker at the actual photographing.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a camera-integrated video tape recorder that integrates a video camera and a video tape recorder.

2. Description of the Related Art In recent years, the penetration rate of camera-integrated video tape recorders (hereinafter abbreviated as camera VTR) has exceeded 10%, and the time has come for a full-scale increase in demand.

At the same time, camera VTRs themselves began to be used for a variety of purposes, and the phenomenon of screen flickering under discharge tube light sources (hereinafter referred to as
Many problems have also occurred, such as the flicker phenomenon. For example, if you use a camera VTR to take pictures under discharge tube light sources such as fluorescent lights in a 50Hz area, NTSO
In the case of a camera VTR using this method, the period of one field is 1/
60 seconds, and at this timing the charge storage type image sensor (
(hereinafter abbreviated as "can"), the photoelectrically converted charge is stored in the fluorescent lamp, which repeats blinking at a cycle of 1/1oO second, and the flicker phenomenon occurs because the amount of charge differs for each field. It is the cause of the occurrence.

Conventionally, as a technology to eliminate this flicker phenomenon, the method of removing flickering phenomenon has been to calculate
Because the above flickering phenomenon occurs at a cycle of 20 seconds,
A method has been devised to reduce the flicker by correcting the difference in the amount of charge during this period.

On the other hand, there is also a camera VTR that allows the user to change the shutter speed of the camera from 1/60 seconds to 1/10 degrees at a time when the user detects the flicker phenomenon to eliminate the flicker.

Problems to be Solved by the Invention However, in the above-mentioned method, a circuit configuration is required to accurately convert the amount of light emitted from the fluorescent lamp into an electric charge and to maintain the electric potential at that time for a period of 1/20 seconds. is complicated, and it is difficult to accurately correct variations in the potential of photoelectrically converted charges. Additionally, if you manually change the camera's shutter speed immediately after you start recording, flickering may be recorded in the first recorded video depending on the timing of the change, and you may end up wasting your tape. .

Another problem is that it is troublesome to have to check whether or not a flicker phenomenon is occurring every time a photograph is taken with the camera VTR.

Means for Solving the Problems In view of the above-mentioned problems, the present invention provides a solution to flicker under a discharge light source.
A flicker detection means detects a phenomenon and replaces it with an electric signal, and a flicker detection command outputted from this flicker detection means is inputted, and a shutter speed switching command is outputted. system control means for controlling the system so that recording does not start until the shutter speed is reliably switched; and shutter speed switching means for receiving the shutter speed switching command and setting the shutter speed to a predetermined shutter speed. It is.

According to the above-described structure, the system control means automatically provides the optimum shutter speed in response to a signal from the flicker detection means even if a flicker phenomenon occurs during movie shooting. In addition to eliminating the flicker phenomenon, by having the system control means manage the timing of recording start, it is possible to prevent the unnecessary recording of images in which the flicker phenomenon has occurred by mistake. In addition, to compensate for the lack of light in the camera image caused by increasing the shutter speed, by adjusting the camera sensitivity to match the shutter speed, the camera image is automatically set to be no different from a normal image. becomes possible.

The user can now take pictures without being affected by the flicker phenomenon.

EXAMPLES Hereinafter, examples of the present invention will be described with reference to the drawings. FIG. 1 shows a block diagram of a camera VTR in a first embodiment of the present invention. In FIG. 1, 11 is a discharge tube light source such as a fluorescent lamp, 12 is a flicker detection means for detecting a flicker phenomenon that occurs when a subject is illuminated by the illumination of the discharge tube light source, and 13 is the flicker detection means. The shutter speed is switched by decoding the flicker detection command 16 output from 12,
14. A system control means for controlling the overall operation of the movie, such as recording and playback; 14. C. Shutter speed switching means inputs the shutter speed switching command 16 outputted from the system control means 13 and sets the shutter speed to a predetermined shutter speed.

The operation of this embodiment configured as described above will be explained below using FIG. 1.

First, when a camera VTR attempts to photograph an object illuminated by a discharge tube light source 11 in the 50 Hz area, the flicker detection means 12 built into the camera VTR detects the difference in light absorption input to the can during each field time. Flicker can be detected by measuring the potential difference between the photoelectrically converted charges.
The phenomenon is detected and a flicker detection command 15 is output. Next, the system control means 13 controls the flicker detection means 1.
Immediately after decoding the flicker detection command 16 outputted from the shutter speed switching means 14, a shutter speed switching command 16 is outputted to act on the shutter speed switching means 14 to eliminate the flicker phenomenon.

In addition, even if an attempt is made to start recording before the shutter speed has been reliably switched, the process is controlled so that the operation is not accepted, thereby preventing erroneous operations that may be recorded as a flicker phenomenon. We will also do moreover,
Immediately upon inputting the shutter speed switching command 16 outputted from the system control means 13, the shutter speed switching means 14 changes the shutter speed of the camera section from the current 1/6o second to 1/1o second.

By instantaneously changing the time in seconds, it is possible to provide a camera image free of flicker.

As described above, according to this embodiment, the flicker detection means 12 detects the flicker phenomenon and outputs the flicker detection command 16, and the flicker detection command 16
The system control means 13 decodes the shutter speed and outputs the shutter speed switching command 16, and performs control so that the recording start operation is reliably shifted after switching to a predetermined shutter speed; and from the system control means 13; By providing a shutter speed switching means 14 that sets the shutter speed to a speed at which no flickering phenomenon occurs in response to the outputted shutter speed switching command 1e, the user of the camera VTR can avoid worrying about the flickering phenomenon during actual shooting. It can be used without causing any damage, and even if a flicker phenomenon occurs, it can be reliably removed with a simple circuit configuration.

Next, a second embodiment of the present invention will be described with reference to the drawings.

FIG. 2 is a block diagram of main parts showing a second embodiment of the present invention. In FIG. 2, 21 is a discharge tube light source such as a fluorescent lamp, 22 is a flicker detection means for detecting the flicker phenomenon that occurs when a subject is illuminated by the illumination of the discharge tube light source, and 23 is the flicker detection means. It decodes the flicker detection command 26 output from 22 and outputs a command to switch the shutter speed, and at the same time outputs a camera sensitivity control command 27 to adjust the camera sensitivity suitable for the shutter speed, and further records the video.・System control means for controlling the overall operation of Moohy such as playback, and 24 is a camera sensitivity control means for inputting the camera sensitivity control command 27 outputted from the system control means 23 to set the optimal camera sensitivity for the shutter speed. ,2
Reference numeral 6 denotes a shutter speed switching means for inputting the shutter speed switching command 2B outputted from the system control means 23 and setting the shutter speed to a predetermined shutter speed.

The operation of the second embodiment of the present invention configured as described above will be explained.

First, similarly to the explanation of the first embodiment above, an object illuminated by the discharge tube light source 21 in the 50Ilz area is photographed using the camera V.
When an attempt is made to take a picture with the TR, a flicker detection means 22 built into it detects a flicker phenomenon and outputs a flicker detection command 26. Next, upon decoding the flicker detection command 26 outputted from the flicker detection means 22, the system control means 23 immediately outputs a shutter speed switching command 2B to the shutter speed switching means 26 to eliminate the flicker phenomenon. Work. At the same time, a camera sensitivity control command 27 is outputted so that even after switching to the above-mentioned shutter speed, a sensitivity equivalent to the brightness in normal use can be obtained.

In addition, even if an attempt is made to start recording before the shutter speed has been properly switched or the camera sensitivity has been changed to a predetermined setting value, the operation is controlled so as not to be accepted, thereby preventing erroneous flickering. - It also performs processing to prevent erroneous operations, such as recording images where a phenomenon has occurred or images that are slightly darker than usual on tape. Further, as soon as the shutter speed switching command 28 outputted from the system control means 23 is input, the shutter speed switching means 26 instantly changes the shutter speed of the camera section from the current 1/60 second to 1/100 second. By changing this, it is possible to provide a camera image free from flicker. Further, the system control means 2
Immediately after inputting the camera sensitivity control command 27 outputted from the camera sensitivity control means 241/i, the camera sensitivity control means 241/i sets the brightness of the camera image to the same sensitivity as normal, and controls the change in brightness and darkness regardless of the switching of the shutter speed. No pictures can be provided.

As described above, according to the second embodiment of the present invention, the flicker detection means 22 detects the flicker phenomenon and outputs the flicker detection command 26,
It decodes the detection command 26 and outputs the shutter speed switching command 2B, and also outputs the camera sensitivity control command 27, and the recording start operation is performed after switching to a predetermined shutter speed or after the camera sensitivity has reached a predetermined value. The system control means 23 performs control to ensure that the change is made to the set value of , and the shutter speed switching command 28 outputted from the system control means 23 controls the shutter speed so that no flicker phenomenon occurs. The brightness of the camera image is set to the same sensitivity as normal by the shutter speed switching means 26 and the camera sensitivity control command 27 output from the system control means 23, and the brightness and darkness are maintained regardless of the shutter speed switching. By providing a camera sensitivity control means 24 that controls IJ so that there is no change in IJ, the user of the camera VTR can use it without worrying about the flicker phenomenon during actual shooting.

In addition, even if a flicker phenomenon occurs, it can be reliably removed with a simple circuit configuration, and
We offer an innovative camera VTR that automatically adjusts the camera sensitivity so that even when the brightness of the camera image changes due to switching the shutter speed, it returns to the normal brightness so that images with different brightness are not recorded. It becomes possible.

Effects of the Invention As described above, the present invention provides a flicker detection means for detecting a flicker phenomenon under a discharge light source and replacing it with an electric signal;
A flicker detection command outputted from this flicker detection means is input, a shutter speed switching command is outputted, and the control is controlled so that the recording start operation does not proceed until the shutter speed is surely switched by the shutter speed switching command. a system control means;
a shutter speed switching means for setting a predetermined shutter speed in response to the shutter speed switching command; and a shutter speed switching means for setting the shutter speed to a predetermined shutter speed in response to the flicker detection command output from the flicker detection means; Along with outputting a switching command,
The camera sensitivity control command is output, and the recording start operation is continued until the shutter speed is reliably switched by the above shutter speed switching command or the camera sensitivity optimal for the predetermined shutter speed is set by the above camera sensitivity control command. The camera sensitivity control system includes the system control means for controlling the camera so as not to shift, and the shutter speed switching means for receiving the shutter speed switching command and setting the shutter speed to a predetermined shutter speed.
By providing a camera control means that inputs a command and sets camera sensitivity suitable for a predetermined shutter speed, it is possible to prevent the signal from the flicker detection means even if a flicker phenomenon occurs during shooting with a camera VTR. In response, the system control means automatically provides an optimal shutter speed to eliminate the flicker phenomenon, and
By having the system control means manage the timing of recording start, it is possible to prevent the unnecessary recording of videos in which a flickering phenomenon has occurred by mistake. Also,
In order to compensate for the lack of light in the camera image caused by increasing the shutter speed, the above system control means automatically adjusts the camera sensitivity to match the shutter speed to automatically produce a camera image that is no different from a normal image. It can also be set, allowing the user to take pictures without being affected by the flicker phenomenon.

[Brief explanation of drawings]

FIG. 1 is a block diagram of the main parts of a camera VTR according to the first embodiment of the invention, and FIG. 2 is a block diagram of the main parts of the second embodiment of the invention. 11.21...discharge sightseeing source, 12, 22...
... Flicker detection means, 13.23 ... System control means, 14.25 ... Shutter speed switching means, 24 ... Camera sensitivity control means, 15, 26 ...Flicker detection command,
16, 28... Shutter speed switching means, 27... Camera sensitivity control command.

Claims (2)

[Claims] (1) Detecting the flickering phenomenon of the screen under the discharge tube light source,
A flicker detection means that replaces it with an electric signal and a flicker detection command output from this flicker detection means are input, a shutter speed switching command is output, and recording is started until the shutter speed is reliably switched by the shutter speed switching command. 1. A camera-integrated video tape recorder comprising: a system control means for controlling the camera so as not to shift to operation; and a shutter speed switching means for receiving the shutter speed switching command and setting the shutter speed to a predetermined shutter speed. (2) The system control means receives the flicker detection command output from the flicker detection means, outputs a shutter speed switching command, and outputs a camera sensitivity control command for controlling the camera sensitivity control means, and switches the shutter speed. The camera shall be configured so that the recording start operation does not proceed until the shutter speed is reliably switched in response to a command, or the optimal camera sensitivity for a predetermined shutter speed is set in accordance with the camera sensitivity control command. The camera-integrated videotape recorder according to claim 1, characterized in that: