Electronic video recording device having a monitor screen on the rear face and a rotary video recording camera attached to the main body

An electronic video recording device has a video recording camera for converting optical information received through an object lens into electronic video information, a monitor screen for displaying electronic video information output from the video recording camera, and a main body having a monitor screen and a control panel for operating the video recording camera. The main body has the monitor screen on a rear face, control panel around a first side face, and a rotary shaft of the video recording camera on a second side face in which a rotary shaft is disposed in a direction approximately perpendicular to the second side face. An incident optical axis of the object lens on the video recording camera is approximately perpendicular to the rotary shaft of the rotary mechanism so that the object lens faces downward when in a housed configuration.

FIELD OF THE INVENTION
 The present invention relates to the field of electronic video recording
 devices including video tape recorders and electronic cameras employing
 large monitors such as liquid crystal displays.
 BACKGROUND OF THE INVENTION
 A broad range of forms of electronic video recording devices including
 video tape recorders and electronic cameras have recently been developed.
 In particular, video recording devices with large monitors for recording
 the camera operator while providing direct feedback on a screen visible to
 the camera operator, so-called self-recording (or facing recording), are
 drawing more attention.
 A video recording device of the prior art related to the present invention
 is explained next.
 FIGS. 3A to 3C show perspective views of the electronic video recording
 device of the prior art. FIG. 3A shows a front perspective, and FIGS. 3B
 and 3C show back perspectives. A video recording camera 101 is disposed
 around an upper corner of a front face 102a of a main body 102, and the
 video recording camera 101 has an object lens 103. Optical information
 entering the video recording camera 101 through the object lens 103 is
 converted to electronic video information. The main body 102 records the
 electronic video information output from the video recording camera 101 on
 a housed video tape (not illustrated). A monitor 105 converts the
 electronic video information output from the video recording camera 101 or
 the electronic video information reproduced from a recorded video tape
 into optical information, and displays it on a monitor screen 105a. The
 monitor 105 is, as shown in FIG. 3C, rotatably attached to the main body
 102 with a rotary mechanism disposed at an upper part of the main body
 102. A microphone 106 is disposed beneath the object lens 103 on the front
 face 102a of the main body 102 for recording sound from approximately the
 same direction as the optical axis of the object lens 103. The main body
 102 records sound information, along with the aforementioned electronic
 video information, on a video tape.
 The operation of the electronic video recording device of the prior art as
 configured above is explained next.
 In ordinary recording, that is, when the camera operator records subjects
 other than himself/herself by looking at a monitor screen, the object lens
 103 is facing the subject, as shown in FIGS. 4A to 4C, and the camera
 operator can confirm what is being recorded by looking at the monitor
 screen 105a. Since the monitor 105 is rotatable away from the main body,
 the camera operator can easily look at the monitor screen 105a at any
 angle particularly at an angle which allows recording from a high position
 downward (so-called high angle, as shown in FIG. 4A), to record ordinarily
 by holding the electronic video recording device around in front of the
 chest (the so-called chest angle shown in FIG. 4B), and to record from a
 low position upward (the so-called low angle shown in FIG. 4C).
 In "self-recording" in which the camera operator is recorded while looking
 at his/her own image on the monitor screen 105a, the camera operator can
 confirm what to be recorded on the monitor screen 105a by rotating the
 monitor 105 to the front to the side of the object lens 103 because the
 monitor 105 is rotatable apart from the main body 102. As already known,
 some existing devices are equipped with the function of inverting the
 video image on the monitor screen 105a by detecting the rotation angle.
 Another example of the prior art is an electronic video recording device in
 which the camera operator operates and holds an area of the recording
 camera by hand, and the monitor is rotatably supported by the video
 recording camera together with the main body.
 The above configurations of the prior art, however, have the following
 inconveniences:
 1) To secure the distance required by the optical system of the video
 recording camera and also assure that the thickness of the main body is
 sufficient to allow it to be held comfortably in the hand, the length of
 the video recording camera needs to be longer than the thickness of the
 main body, making the camera protrude significantly from the main body.
 2) Since the object lens and the main body are held toward the direction of
 the subject to be recorded, the angle of the wrist required to hold the
 device changes according to recording angle, and there are some angles
 which result in difficulties in holding the device.
 3) Since the object lens always remains in a lateral position even when not
 recording anything, the object lens is likely to be directly exposed to
 bright light including direct sunlight, resulting in flare and other
 problems characteristic of CCD image pickup elements in the video
 recording camera, or dust is likely to attach to the object lens.
 SUMMARY OF THE INVENTION
 The present invention offers an electronic video recording device which
 enables the securing of a sufficient distance between the optical system
 of the video recording camera while keeping the thickness of the main body
 to a level easy to hold when the video recording camera is housed; enables
 the monitoring of the picture being recorded without changing the wrist
 angle too much while holding the device at a range of recording angles;
 and provides a configuration whereby the object lens is not directly
 exposed to bright light including direct sunlight and is protected from
 dust accumulation when the device is not being used for recording.
 The electronic video recording device of the present invention thus
 comprises a video recording camera for converting optical information
 entering from the object lens into electronic video information, a monitor
 screen for displaying electronic video information output from the video
 recording camera, and a main body which has a control panel for operating
 the video recording camera and a monitor screen. The main body has the
 monitor screen located on its rear side, the control panel on its first
 side face, and a rotary mechanism of the video recording camera on its
 second side face. The rotary mechanism has a rotary shaft in a direction
 approximately perpendicular to the second side face. The incident optical
 axis of the object lens on the video recording camera is approximately
 perpendicular to the rotary shaft of the rotary mechanism, and the rotary
 shaft is configured in a way which allows the object lens to face downward
 when housing the video recording camera. This enables the securing of a
 sufficient distance for the optical system of the video recording camera,
 realizes a comfortable thickness for holding the main body when the video
 recording camera is housed, and allows the monitoring of the picture to be
 recorded at any recording angle without changing the wrist angle when
 holding the device. In addition, the object lens is protected from dust
 and not directly exposed to bright light, such as direct sunlight, except
 during recording.
 Furthermore, the electronic video recording device of the present invention
 comprises a video recording camera for converting optical information
 entering from the object lens to electronic video information, a monitor
 screen for displaying electronic video information output from the video
 recording camera, and a main body which has a control panel for operating
 the video recording camera and a monitor screen. The main body has the
 monitor screen located at its rear side, a rotary mechanism of the video
 recording camera on its second side face in which a rotary shaft is
 disposed in a direction approximately perpendicular to the second side
 face, and the control panel on its first side face. This enables single
 hand recording without placing too much strain on the hand holding the
 main body.
 The electronic video recording device of the present invention still
 further comprises a video recording camera for converting optical
 information entering from the object lens into electronic video
 information, and a main body which has a control panel for operating the
 video recording camera and a rotary mechanism for rotatably supporting the
 video recording camera. The weight ratio of the video recording camera and
 the main body is 1:3 to 1:7. This enables single hand recording without
 placing too much strain on the hand holding the main body. At the same
 time, there is no need for a large and robust rotary mechanism because the
 video recording camera is lighter than the main body, and this allows the
 device to be smaller.

DESCRIPTION OF THE PREFERRED EMBODIMENT
 An exemplary embodiment of the present invention is explained with
 reference to FIGS. 1A to 2C.
 FIG. 1A shows an exemplary embodiment when an electronic video recording
 device of the present invention is housed. A video recording camera 1 is
 an approximate rectangular parallelepiped shape, and is disposed at a
 right side face 2r (a second side face) of a main body 2. A control panel
 7 consisting of control switches for operating the video recording camera
 1 to record video images is disposed on a top face 2u of the main body 2
 preferably at a position far from the video recording camera 1. A
 microphone 6 is disposed on a lower part of a front face 1a of the video
 recording camera 1. During recording, the camera operator holds around a
 left side face 2d (a third side face) and its nearby area of the main body
 2.
 FIG. 1B shows an exemplary embodiment when an electronic video recording
 device of the present invention is used for recording. Compared to FIG.
 1A, during housing, FIG. 1B shows the video recording camera 1 in a
 position when it is rotated 90.degree. by a rotary mechanism 4 against the
 main body 2. The video recording camera 1 has an object lens 3 disposed on
 its bottom face 1c, and optical information entering from, i.e., received
 through the object lens 3 is converted into electronic video information.
 The main body 2, the same as that of the prior art, records electronic
 video information output from the video recording camera 1 onto a video
 tape (not illustrated), and houses a battery (not illustrated) for
 supplying power to the video recording camera 1 and power required for
 recording. The rotary mechanism 4 is provided on the main body 2 at an
 upper part of the right side face 2r (the second side face) of the main
 body 2 for supporting the video recording camera 1 by a side face 1b (a
 first side face) facing the main body 2 so that the bottom face 1c of the
 video recording camera 1 can be rotated. The first side face 1b and the
 second side face 2r contact or are adjacent to each other with just a
 little distance. The rotary mechanism 4 provides a rotating connection
 between the video recording camera 1 and the main body 2 while keeping an
 appropriate rotary resistance therebetween. A rotary shaft 4a is disposed
 approximately perpendicular to the first side face 1b and the second side
 face 2r . The microphone 6 is disposed at a lower part of the front face
 1a of the video recording camera 1 for collecting sound from approximately
 the same direction as the optical axis of the object lens 3 and recording
 sound information, as with the aforementioned electronic video
 information, onto a video tape by the main body.
 As shown in FIGS. 1C and 1D, a monitor screen 5 is disposed on the rear
 face 2c of the main body 2, and displays electronic video information
 output from the video recording camera 1 and electronic video information
 reproduced from a recorded video tape in the form of optical information,
 as in the prior art. The control panel 7 comprises a group of operation
 switches for operating the video recording camera 1 to record video
 images, and is disposed on the top face 2u near the left side face 2d
 preferably on the top face 2u of the main body 2 so that the camera
 operator can hold an area of the third side face 2d and adjoining rear
 face 2C and front face 2a with the right hand while operating the control
 panel 7 for recording video images. It is preferable to configure the
 monitor screen 5 on the rear face 2c away from the third side face 2d of
 the main body 2 so that the monitor screen 5 will not be covered with the
 hand when the camera operator holds the main body. It is still more
 preferable to configure the bottom face 1c of the video recording camera
 1, where the object lens 3 is disposed, at a level above the bottom face
 2e of the main body 2 so that the video recording camera 1 can be rotated
 against the main body 2 even if the main body 2 is placed on a flat table
 as shown in FIGS. 1A to 1D.
 The difference in the configuration of this exemplary embodiment of the
 present invention compared to the prior art is that the object lens 3 is
 disposed on the bottom face 1c of the video recording camera 1, and the
 microphone 6 is disposed at a lower part of the front face 1a of the video
 recording camera 1. Furthermore, the rotary mechanism 4 is disposed at an
 upper part of the second side face 2r of the main body 2 for supporting
 the main body 2 held by the camera operator for monitoring a subject to be
 recorded and the video recording camera 1 in such a way that both are
 rotatable. In other words, with respect to the video recording camera 1,
 the rotary shaft 4a of the rotary mechanism 4 is disposed away from the
 bottom face 1c where the object lens 3 is disposed and a lower part of the
 front face 1a where the microphone 6 is located. This configuration
 changes the distance of the optical system required for the video
 recording camera 1 from that of the prior art, and thus the distance can
 be made longer than the thickness of the main body 2, allowing more
 flexibility in designing the optical system. Accordingly, the optical
 system can be configured with, compared to the prior art, more functions
 and higher performance.
 In fact, the thickness of the main body for comfortable holding by the
 camera operator is between 20 mm and 60 mm, preferably between 30 mm and
 50 mm, although this dimension may depend on the weight of the electronic
 video recording device. To configure an optical system for video recording
 including CCD elements within this length, it may be, for example,
 necessary to restrict the zoom ratio or omit a zoom function from the
 optical system, or design a monofocus system. The curvature (NA) of the
 lens of the optical system may also need to be made extremely large. With
 this exemplary embodiment, however, the length of the optical system, or
 the video recording camera, is not restricted by the thickness of the main
 body. In addition, since the video recording camera is housed in the same
 direction as the vertical direction of the monitor on the main body, the
 size of the monitor can also be made larger.
 A lighter electronic video recording device is naturally easier to operate,
 and also it will be easier to operate if the weight of the main body to be
 held by the camera operator is heavier than other parts supported by the
 rotary mechanism. The preferable weight ratio between these two parts is:
 (Weight of the part supported by the rotary mechanism): (Weight of the main
 body held by the camera operator)=1:3 to 1:7.
 In this exemplary embodiment, the video recording camera 1 supported by the
 rotary mechanism 4 can be made proportionally much lighter than the main
 body 2 comprising those sections including a video tape recorder (VTR)
 unit for recording video information, battery, and control panel because
 the video recording camera can be configured with an optical system
 including CCD elements. Accordingly, the above preferable weight ratio can
 be satisfied with the present invention. In addition, a large and robust
 rotary mechanism for holding the video recording camera may not be
 required.
 The operation of the electronic video recording device as configured above
 is explained next.
 In ordinary recording, the video recording camera 1 is rotated to rotate
 the object lens 3 to face a subject, and the camera operator can confirm
 what is being recorded by looking at the monitor screen 5. Since the main
 body 2 and the video recording camera 1 are rotatable to any angle as
 shown in FIGS. 2A to 2C, the camera operator can always look at the
 monitor screen 5 from directly in front and almost at a right angle when
 recording at high angle (FIG. 2A), chest angle (FIG. 2B), and low angle
 (FIG. 2C). In other words, the main body 2 can be held by the right hand
 as shown in FIGS. 2A to 2C and angle of the video recording camera 1 can
 be changed to face a subject with the left hand because the rotary
 mechanism has an appropriate rotary resistance to hold the video recording
 camera 1 at an adjusted angle. Even if a rotating angle of the video
 recording camera 1 is changed to face a subject and the main body 2 is
 held in a position to look at the monitor screen from directly in front,
 the wrist angle of the hand holding the main body will not change much.
 This permits a subject recording without keeping the wrist at an unnatural
 angle for holding the main body 2.
 Also in "self-recording," the camera operator can confirm himself/herself
 on the monitor screen 5 by rotating the main body 2 and the video
 recording camera 1 to make the object lens 3 approach the rear face 2c on
 which the monitor screen is disposed.
 In addition, since the optical axis of the object lens 3 is along the
 lengthwise direction of the video recording camera 1, the object lens 3
 can be more easily adjusted toward the direction of a subject compared to
 the prior art. Since the microphone 6 is disposed apart from the main body
 2, the microphone 6 is unlikely to record operating noise generated from
 the main body 2. Furthermore, since the camera operator can operate and
 hold the main body 2 only with the right hand and the operation switches
 are disposed on the top face 2u near the third side face 2d of the main
 body away from the video recording camera 1, operating sound of the camera
 operator is also unlikely to be recorded by the microphone 6.
 Next, when the electronic video recording device is not used for recording
 which means during reproduction of recorded video images or when the video
 recording camera 1 is housed, the object lens 3 of the video recording
 camera 1 is protected from bright light including direct sunlight, thereby
 avoiding damage to performance of the internal CCD image pickup elements,
 and protected from dust by rotating the video recording camera 1 against
 the main body 2 to face the object lens 3 downward.
 By rotating the main body 2 and video recording camera 1 for housing, the
 entire device is housed to a rectangular parallelepiped shape without any
 protrusion, which is extremely convenient for storage. Furthermore, the
 video recording camera 1 can be used as a leg for supporting the tilted
 main body 2 by rotating the main body 2 and the video recording camera 1
 so that reproduced video images can be comfortably watched on the monitor
 screen 5, placing the entire device somewhere without holding the main
 body 2 by hand.
 As described above, the present invention has the following significant
 effects.
 The distance of an optical system of the video recording camera can be
 determined without being restricted by the thickness of the main body.
 This permits improved flexibility in designing for realizing the optical
 system with more and better functions and higher performance by securing a
 longer distance for the optical system compared to that of the prior art.
 The optical axis of the object lens extends along the lengthwise direction
 of the video recording camera. This facilitates adjustment of the object
 lens to a subject compared to that of the prior art. Disposition of the
 microphone apart from the main body also prevents collection of operating
 noise generated from the device or caused by the camera operator.
 The object lens of the video recording camera is configured to face
 downward by rotating the video recording camera and the main body during
 reproduction and housing. This prevents damage to the performance of the
 internal CCD image pickup elements due to being exposed to bright light
 such as direct sunlight and protects the object lens from dust.
 The electronic video recording device of the present invention turns into
 an extremely convenient shape for housing by rotating the main body and
 video recording camera.
 The monitor screen can mostly be viewed at a right angle by rotating the
 video recording camera, without changing the wrist angle of the hand
 holding the main body, during recording at any angle.
 The above explanation of the electronic video recording device refers to a
 video tape recorder, using a video tape as a recording medium, as an
 example. The configuration of the present invention is applicable to many
 other types of devices including electronic cameras for recording images
 on recording elements such as a semiconductor memory, and TV cameras which
 transmit electronic information of recorded images to other video
 information processing devices via wire or radio without using any kind of
 recording medium.
 The preferred embodiments described herein are therefore illustrative and
 not restrictive. The scope of the invention being indicated by the
 appended claims and all modifications which come within the true spirit of
 the claims are intended to be embraced therein.