Monitoring apparatus

Abstract

A monitoring apparatus includes an image-forming optical system aimed forward, an image sensor, an antenna, a first circuit board, a waveguide, an upper case, an information-processing circuit, a second circuit board, a connector, and a power-supply circuit. The connector is disposed at a rear side relative to the image-forming optical system. The power-supply circuit includes at least one capacitor, and a capacitor that is positioned at a highest location out of all of the at least one capacitor is disposed at a rear side relative to the image-forming optical system, which prevents the capacitor from obstructing the visual field of the image-forming optical system. Thus, the image-forming optical system is able to be located close to the power-supply circuit because the monitoring apparatus is very small in height.

What is claimed is: 
     
         1 . A monitoring apparatus comprising:
 an image-forming optical system aimed in a first direction;   an image sensor positioned at a focal point focus of the image-forming optical system;   an antenna member including an antenna with a main lobe that extends in the first direction, the main lobe being a radiating pattern of the antenna member;   a radio frequency circuit;   a first circuit board including the radio frequency circuit thereon;   a waveguide connecting an output end of the radio frequency circuit and the antenna;   an upper case positioned at a first side in a second direction of the antenna member,   the second direction being different from the first direction, the upper case including a flat portion;   an information-processing circuit;   a second circuit board including the information-processing circuit thereon;   a radio frequency circuit signal line connecting the radio frequency circuit to the information-processing circuit;   an image signal line connecting the image sensor to the information-processing circuit;   a connector electrically connected to the second circuit board;   a power-supply circuit providing DC power to the information-processing circuit and the radio frequency circuit; and   a cover including a plate member made of resin disposed at a first side in the first direction to the antenna member; wherein   the flat portion of the upper case is inclined in a direction in which the flat portion of the upper case is closer to a central axis of the main lobe of the antenna member at the first side in the first direction than at a second side in the first direction of the flat portion of the upper case;   the second circuit board is positioned between the upper case and the antenna member;   the upper case includes, in a middle of the flat portion, a visual field window that includes a notch or a hole;   an optical axis of the image-forming optical system passes through the visual field window;   the image-forming optical system is fixed to the upper case;   the flat portion is positioned at a second side in the second direction with respect to a visual field of the image-forming optical system;   the connector is positioned at the second side in the first direction relative to the image-forming optical system;   the power-supply circuit includes at least one capacitor;   the cover has a constant thickness and has a square or substantially square shape in a front view;   the cover includes a front portion and a lower-surface portion;   the front portion is disposed facing the antenna member;   the front portion is inclined such that the lower side thereof recedes backward with respect to the antenna member; and   the lower-surface portion extends to the antenna member at the lower edge of the cover, covering a portion of the lower surface of the antenna member.   
     
     
         2 . The monitoring apparatus of  claim 1 , wherein,
 the antenna member and image-forming optical system arranged in a line in the first direction;   the antenna member includes a portion for radiating and receiving an electromagnetic wave; and   the portion is located on the lower side of the image-forming optical system and in front of the image-forming optical system in the first direction.   
     
     
         3 . The monitoring apparatus of  claim 1 , wherein,
 a lower edge of the cover is positioned at a front side relative to an upper edge of the cover in a central-axis direction of the main lobe; and   Formula 1 is satisfied,   
       
         
           
             
               
                 
                   
                     
                       
                         
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       with d being a thickness of the cover, ε being a relative dielectric constant of a resin material constituting the cover, θ being an angle defined by a central axis of the main lobe and a normal to a surface of the cover, A being a wavelength of an electromagnetic wave in vacuum at a frequency the radio frequency circuit outputs, and m being a natural number. 
     
     
         4 . The monitoring apparatus of  claim 1 , wherein
 the antenna member is directly fixed to the upper case; and   the waveguide and the first circuit board are directly fixed to the antenna member.   
     
     
         5 . The monitoring apparatus of  claim 1 , further comprising a lower case covering a surface of the antenna member at the second side in the second direction. 
     
     
         6 . The monitoring apparatus of  claim 2 , further comprising a lower case covering a lower surface of the antenna member at the second side in the second direction.