Abstract:
An indicator provided on the surface of a video camera for warning of the occurrence of a matter which interrupts the recording; for example, dew on a recording head and the approach of a tape end. These occurrences during a recording operation must be informed to a subject as well as to a photographer who stands without looking into a finder of the video camera.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the invention 
     This invention relates to a video camera including an indicator on the surface of the video camera. 
     2. Description of the prior art 
     It is known that indicators on the surface of a video camera indicate various warnings for a photographer. 
     For example, a video camera indicates a count of moving tape on a part of a liquid crystal display on the side surface of a video camera, detects that the last five minutes of the tape for recording is come and then warns that on another part of the liquid crystal display; detects that the voltage of a power source is below a predetermined level and then warns that on another part of the liquid crystal display; and detects dew on a recording head of the video camera and then warns that on another part of the liquid crystal display. 
     However, there is no video camera having an indicator on the surface of the video camera which indicates whether recording is being operated normally or the end of a medium for recording is near. It is important to warn that the end of the medium for recording comes during the recording operation to the subject or the photographer who stands without looking into a finder, because the subject should prepare himself for the ending, and the photographer should prepare himself for the ending and next recording. And there is no video camera having an indicator on the surface of the video camera which indicates whether recording is being operated normally or there is dew on a recording head. It is also important to warn the occurrence of dew during the recording operation. If dew is condensed on the recording head, the relation between the recording head and a medium becomes unstable and further recording operation should be stopped. So the photographer and the subject should be informed of the occurrence of dew during the recording operation 
     And in the aforementioned video camera, many elements in the liquid crystal display are required for each detection and large space for the elements is needed. Moreover, one who looks at a certain part of the liquid crystal display can not know the occurrence of another warning. 
     It is also known that a video camera consists of the main body and the finder body which is angularly displaceable on the main body, and an indicator for indicating to a subject that recording is being operated is provided on the main body which provides other members, e.g. lens, microphone, grip, connecting terminals and switches. 
     If the indicator is provided on the main body, it is difficult to distinguish the indicator from the various members also provided on the main body, and the surface of the main body becomes in further confusion. On the other hand, if the indicator is provided on the finder body, it is difficult that one can see the indicator from the front irrespective of the position of the finder body: between the eye level position and the waist level position. 
     SUMMARY OF THE INVENTION 
     It is therefore a first object of this invention to provide a video camera that one can know whether the recording is operated normally or there is a danger of further recording because of approach of the end of the recording medium with one indicator on the video camera, or to provide a video camera that one can know whether the recording is operated normally or there is a danger of further recording because of dew with one indicator. 
     In order to achieve the first object, first, there are provided means for detecting the end of the medium for recording; an indicator which normally indicates whether the recording is operated or not on the surface of a video camera; and means for changing the indication state in accordance with the detection of the detecting means. Second, there are provided means for detecting dew on a recording head; an indicator which normally indicates whether the recording is operated or not on the surface of a video camera; and means for changing the indication state in accordance with the detection of the detecting means. 
     It is a second object of this invention to provide a video camera which consisting of a main body and the finder body which is angularly displaceable on the main body, and provide an indicator on the finder body, not on the main body, which provides various things so that one can see the indicator easily from the front irrespective of displacing of the finder body. 
     For the second object, there is provided a surface which can be seen from the front irrespective of the position of the finder body between the eye level and the waist level, and the indicator is provided on said surface. 
     It is a third object of this invention to provide a video camera having two kinds of indicators, one is provided for warning there is a danger of recording; the other is provided for indicating a kind of matter causing the danger. 
     For the third object the indicator for warning is provided on the surface of the video camera. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     This invention will become more fully understood from the detailed description given below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of this invention, and wherein: 
     FIG. 1 is a side elevational view of an embodiment of a video camera in accordance with the present invention; 
     FIG. 2 is a front elevational view corresponding with the embodiment of FIG. 1 on the eye level state; 
     FIG. 3 is a front elevational view corresponding with the embodiment of FIG. 1 on the waist level state; 
     FIG. 4 is a schematic circuit diagram of the video camera to operate indicators which are provided outside the video camera and in a finder of the video camera; 
     FIG. 5 is a specified circuit diagram for a part of the diagram of FIG. 4; 
     FIG. 6 (a) is an indication example in the finder for recording; 
     FIG. 6 (b) is an indication example in the finder for voltage drop; 
     FIG. 6 (c) is an indication example in the finder for tape end approach; and 
     FIG. 6 (d) is an indication example in the finder for dew condensation. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The present invention will be described in the following in connection with its embodiment of a one-body type video camera, in which is built camera and recorder, with reference to FIGS. 1 to 6. 
     In these Figures: reference numeral 1 designates a main body of the one-body type video camera; numeral 2 a camera lens for photographing an object; numeral 3 a sound collector microphone for collecting external sounds; and numeral 4 a grip for holding the main body 1 with the right hand of the operator. This grip 4 is arranged with a battery. Moreover: reference numeral 5 designates a band strap for fixing the operator&#39;s right hand on the grip 4; numeral 6 a zoom button for zooming the lens 2; and numeral 7 a trigger button for starting/stopping the photography (i.e., picture recording). First of all, the main switch is turned on, and the (not-shown) recording button is once depressed to cause a paused state (for camera monitoring). After this, the trigger button 7 is depressed to start the photography so that the image taken by the camera lens 2 is recorded by the recording means. Still moreover: numeral 8 designates a light receiving aperture for adjusting the white balance; numeral 9 an external power source terminal; numeral 10 an external microphone terminal; numeral 11 a cassette mounting portion for mounting a cassette having a built-in picture recording tape; and numeral 12 a finder body which will be shortly referred to as a &#34;finder&#34;). This finder 12 is equipped with an eyepiece 13 having a CRT therein, a ring 14 for adjusting the diopter and a projection 31. 
     To this projection 31, there is fixed a lever 32 which is so joined to the main body 1 that it can be turned on a pin 33 between a parallel position and a perpendicular position with respect to the photographic direction In other words, the finder 12 is so attached to the camera body 1 that it can be turned through the pin 33 between the parallel and perpendicular positions with respect to the photographic direction. In FIG. 1, the solid lines indicate the parallel position of the finder 12, and the single-dotted lines indicate the perpendicular position of the finder 12. 
     For the photography, the finder 12 is positioned in parallel with the photographic direction for the eye level as high as the operator&#39;s eye. For the waist level, on the other hand, the CRT can be conveniently viewed from above if the finder 12 is brought to the perpendicular position 
     The finder 12 has its sloped front portion 54 arranged with a red light emitting diode 15, which indicates not only whether or not the main body 1 is in photography but also a warning when the battery voltage drops below a predetermined value (e.g., 9.2 V for the specified main voltage of 9.6 V), when the tape runs to the vicinity (e.g., 2 to 3 minutes before the end) of its tail or when dew is condensed on the rotary cylinder which contacts the tape for recording, as tabulated in the following. 
     
                       TABLE 1______________________________________State of Video Camera               Indication State______________________________________Photography         ONWarning   Voltage Drop  Blink at 4 Hz     Tape End approach     Dew CondensationOthers              OFF______________________________________ 
    
     FIG. 2 is a front elevation showing the video camera in the eye level state. The red light emitting diode 15 is so apart from the main body having the various accessories that it is attractive. 
     FIG. 3 is a front elevation showing the video camera in the waist level state. The finder 12 stands upright but does not conceal the light emitting diode 15. 
     As described above, the operator can visually confirm the indication of the light emitting diode 15 inside of the indication aperture whether the video camera might be in the eye or waist level state. 
     The present embodiment has its indication element exemplified by the light emiting diode, but the present invention should not be limited thereto. 
     In order to control the lighting of the red light emitting diode in accordance with Table 1, the video camera is equipped therein with a lighting control circuit which is constructed, as shown in FIG. 4. 
     A part of circuit components D, E and G shown in FIG. 4 are specified in FIG. 5. 
     In FIG. 5: letter S designates a recording start switch as the trigger button 7; letter A a battery voltage check circuit; letter B a tape end detect circuit; and letter C a dew condensation detector, all of which are connected with a control unit D. Moreover: letter E designates an emission driver; letter F the CRT disposed in the eyepiece 13 of the finder 12; and letter G the light emitting diode 15. 
     The control unit D receives not only the recording start signal from the recording start switch S but also a signal indicating whether or not the battery voltage is below a predetermined level from the battery voltage detector A, a signal indicating whether or not the tape end is near from the tape end detector B, and a signal indicating whether or not there is dew from the dew condensation detector C. In response to these signals, the control unit D issues a signal to the emission driver E and the CRT F. In response to the signal from the control unit D, the emission driver E determines the emission state to excite the light emitting diode G. 
     In response to the signal from the control unit D, on the other hand, the CRT F also accomplishes the corresponding display. 
     In FIG. 5, designated at reference numeral 16 is a first control circuit which is equipped with input terminals a to d and corresponding output terminals e to h. If the detection signals indicating the photography, the battery voltage drop, the tape end and the dew condensation are inputted to the input terminals a to d, respectively, from the circuits S, A, B and C shown in FIG. 4, the first control circuit 16 outputs an H level from the corresponding one or ones of the output terminals e to h. Numeral 17 designates a second control circuit which is made operative: to prepare a control signal for controlling the lighting of the red light emitting diode 15 from both the outputs of the individual output terminals e to h of the first control circuit 16 and the oscillating output of 4 Hz of an oscillator 18; and to output its prepared control signal from its output terminal i. Numeral 19 designates a first OR gate which is made receptive of the outputs from the output terminals f, g and h of the first control circuit 16. Numeral 20 designates a first AND gate which is made receptive of both the output of the output terminal e of the first control circuit 16 and the output of the first OR gate 19 through an inverter 21. Numeral 22 designates a second AND gate which is made receptive of both the output of the first OR gate 19 and the oscillating output of 4 Hz of the oscillator 18. Numeral 23 designates a second OR gate which is made receptive of the outputs of the first and second AND gates 20 and 22. The output of the second OR gate 23 is fed through an inverter 24 and a resistor 25 to the cathode of the red light emitting diode 15. 
     As a result, the first control circuit 16 has all its output terminals e to h held at an L level if none of its input terminals a to d receives any detection signal. Then, all the outputs of the first and second OR gates 19 and 23 and the first and second AND gates 20 and 22 are at the L level. In this state, the red light emitting diode 15 is OFF because its cathode is fed with the inverted output of the L level coming from second OR gate 23. Next, the photography is effected to input the detection signal indicating the operation to the input terminal a of the first control circuit 16. Then, this first control circuit 16 has its output terminal e raised to the H level so that the output of the first AND gate 20 is turned from the L to H levels. As a result, the output of the second OR gate 23 is also switched from the L to H levels, and the red light emitting diode 15 is fed at its cathode with the inverted output of the H level from the second OR gate 23 so that it is turned ON. If, during this photography, any of the detection signals indicating the battery voltage drop, the tape end approach and the dew condensation is generated and fed to any of the input terminals b, c and d of the first control circuit 16, the corresponding one of the output terminals f, g and h of the first control circuit 16 is raised to the high level to switch the output of the first OR gate 19 from the L to H levels. As a result, the output of the first AND gate 20 takes the L level despite the H level is outputted from the output terminal e of the first control circuit 16, and the outputs of the second AND gate 22 and the second OR gate 23 are caused to repeat the L and H levels at 4 Hz by the oscillating output coming from the oscillator 18. Thus, the red light emitting diode 15 is blinked at 4 Hz. Not only during such photography but also in the paused state or at the step of making the main switch (i.e., when the output terminal e of the first control circuit 16 is at the L level) before the photography, the detection signal indicating the battery voltage drop or the dew condensation may be generated and inputted to the corresponding one of the input terminals b and d of the first control circuit 16. Then, the red light emitting diode 15 is also blinked at 4 Hz. The indications of the red light emitting diode 15 corresponding to the output states of the individual output terminals of the first and second control circuits 16 and 17 will be summarized in the following. 
     
                       TABLE 2______________________________________e     f, g, h          i      Indication______________________________________L     all at L         H      OFFH     all of L         L      ONH     one or more at H 4 Hz   Flash at 4 HzL     one or more at H 4 Hz   Flash at 4 Hz______________________________________ 
    
     If one of the dangers of battery voltage drop, tape end approach and dew condensation takes place when the main switch is ON for the photography, the red light emitting diode 15 flashes to make warning to the outside so that the operator can promptly return to the video camera and take proper countermeasures when the visually confirms the warning, even if the stands apart from the camera. 
     At this time, which of the battery voltage drop, tape end approach or dew condensation the warning by the red light emitting diode 15 indicates can be confirmed by inspecting the CRT in the eyepiece 13. Specifically, the CRT is enabled to indicate in the finder: the operation of the photography or the pause; and the warning of the battery voltage drop, the tape end approach or the dew condensation, as illustrated in FIG. 6. For example, the photography is indicated by &#34;REC&#34; in the lower portion of the display screen 26, as shown in FIG. 6(a). For the pause, the indication &#34;REC&#34; is replaced by the indication of &#34;PAUSE&#34;. If, during this photography, the battery voltage drops, a battery mark 28 appears and flashes at 1 Hz above an autofocus photometric frame 27 as the center of the display screen 26, as shown in FIG. 6(b). If, during the photography, the end of the tape as a recording medium comes near, a cassette mark 29 appears and blinks at 1 Hz below the auto-focus photometric frame 27 at the center of the display screen 26, as shown in FIG. 6(c). If, during the photography, the dew is condensed on the rotary cylinder constituting the recorder, a water droplet mark 30 appears and blinked in a position like that of the cassette mark 29, as shown in FIG. 6(d). At this time, the recording operation is interrupted to the paused state. The indications in the finder thus far described will be tabulated in the following. 
     
                       TABLE 3______________________________________State of Video Camera            Indications in Finder______________________________________Photography      RECPause            PAUSEWarning  Voltage Drop   Battery mark blinks at 1 Hz  Tape End coming                 Cassette mark blinks at 1 Hz  Dew Condensation                 Droplet mark blinks at 1 Hz______________________________________ 
    
     Moreover, the control unit D is constructed to accomplish the operations, as enumerated in Table 4, after the warning indications by the red light emitting diode 15 so that there arises no structural disadvantage even if no proper countermeasure is taken after the warnings. 
     
                       TABLE 4______________________________________                      SubsequentWarning        Warning Time                      Operation______________________________________Battery Power ON   Main voltage                          Warn till 8.8 V,Voltage            drops from 9.6                          then Power OFFDrop               to 9.2 V   Pause      Main voltage                          Warn till 8.8 V,              drops from 9.6                          then Power OFF              to 9.2 V   Photography              Main voltage                          Warn till 8.8 V,              drops from 9.6                          then Pause &amp;              to 9.2 V    Power OFFClose to   Power ON   No Warning  No changeTape    Pause      No Warning  No changeEnd     Photography              2 or 3 min. Warn till tape end,              before tape end                          then Unload &amp; StopDew     Power ON   Dew         Warn till dew isCondensed          Condensed   dried   Pause      Dew         Warn till tape end,              Condensed   then Unload &amp; Stop   Photography              Dew         Warn till dew is              Condensed   dried, Pause to                          unload &amp; Stop______________________________________ 
    
     As a result, it is possible to eliminate the disadvantage that the recording means is left in its recording state to have its pinch rollers or the like deformed, even i the battery voltage drops to a level disabling the recording means. There is eliminated another disadvantage that the tape or recording means is left units recording state at its tail and is damaged even the tape comes to the vicinity to its tail during the photography. Further eliminated is a disadvantage that the recording means is left in its recording state so that theater is damaged by the rotary head even if dew is condensed on the rotary head during the photography. 
     Thus, according to the present embodiment, for the ordinary photography by observing the finder, the state of the video camera can be confirmed with the indication in the finder. For either the photography without the observation or the pause of the photography or when the main switch is turned on for the photography, the state of the video camera can be confirmed through the red light emitting diode which is mounted in the camera. When the warning is visually confirmed by the flash of the red light emitting diode, its content can be discriminated by inspecting the finder. Moreover, the camera is prevented from any damage even if no proper countermeasure (such as the replacement of the battery of cassette or the drying of the dew) is taken after the warning. 
     Other modifications are possible without departing from the spirit of this invention and the foregoing description is to be considered as illustrative only and not as limiting the scope of the invention as defined by the appended claims.