Login to reply the answers Post How do you think about the answers? You can sign in to vote the answer. Sign in Noga 1 decade ago Vidicon camera is a term which commonly used for all types of television cameras. Strictly, a vidicon is a TV camera tube in which the target material is made of Sb2S3. The principle of operation of the vidicon camera is typical of that for other types of TV camera tubes, i.
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Login to reply the answers Post How do you think about the answers? You can sign in to vote the answer. Sign in Noga 1 decade ago Vidicon camera is a term which commonly used for all types of television cameras. Strictly, a vidicon is a TV camera tube in which the target material is made of Sb2S3. The principle of operation of the vidicon camera is typical of that for other types of TV camera tubes, i. The vidicon camera tube is also sometimes called a hivicon tube. Television camera or video camera, the camera used in X-ray fluoroscopic and digital imaging for converting the dynamic optical image into a standard video signal.
Because of the recent importance that digital X-ray imaging has assumed, the television camera has been significantly refined to provide improved image resolution, increased dynamic range, and improved temporal resolution over the cameras used in non-medical imaging applications. Colour video cameras are not used in medical X-ray imaging. Points of importance include the light sensor, the image scanner, and the scanning format.
Although many types of video cameras are available, the camera basically consists of a small electronic vacuum tube surrounded by coils focusing coils, horizontal and vertical deflecting coils.
The image receptor target is composed of a thin field of photoconductive material. In one of the most commonly used video cameras, the vidicon, the photoconductive material is usually antimony sulphide Sb2S3 suspended as globules in a mica matrix.
In a plumbicon, the material is lead monoxide PbO. The target is mounted next to a conducting plate the signal plate which is in turn mounted on a glass face plate. Each globule is about 0. The light from the image is focused through the glass plate, the signal plate and mica matrix onto the photoconducting globules, and photoelectrons are emitted in proportion to the intensity of light.
These electrons are attracted to the anode and are immediately removed from the tube. The globules are capacitively coupled to the signal plate, and the residual positive charge on the globules causes current to flow onto the signal plate. After exposure and emission of the photoelectrons, a residual image that is an exact replica of the light image focused on the target is stored in the photoconductor as a positive charge distribution.
The stored image is read out by scanning an electron beam across the globules. The electron beam is emitted from the cathode, which is located at the opposite end of the camera tube from the target.
The cathode is heated indirectly by an internal electric coil. This heating causes electrons to be emitted from the cathode by thermionic emission, creating an electron cloud. These electrons are formed into a beam by the control grid which begins the electron acceleration towards the target.
The electrons are accelerated by a V potential difference toward the anode, which consists of a fine wire mesh in front of the signal plate. The signal plate is at a lower potential than the anode, and the electrons are decelerated as they approach the plate, reaching a net energy of about 25 eV. This decelerating field also straightens the path of the electrons, causing them to strike perpendicularly to the signal plate. The electron beam is focused to a fine point as it hits the target and is scanned over the target by the deflecting coils.
The beam discharges each globule, discharging the capacitor and causing current to flow from the signal plate. This current equals the charge stored in the photoconductor. By scanning the electron beam across the entire surface of the photoconductor, the entire image can be detected. The output signal, the video signal, is a one-dimensional voltage versus time curve presentation of the two-dimensional image. The video signal is amplified and later used in the "reverse" process in a television monitor.
In digital fluoroscopy DF systems, the signal can be digitized and transferred to a computer memory for appropriate processing of the image.
VIDICON AND DIGITAL CAMERA WORKING PRINCIPLES PDF
The chip consists arrays of sensors, which can convert the light into electrical charges. But for higher pixel range and costly cameras mostly CCD technology is used. This light is made to focus on an image sensor which converts the light signals into electric signals. The light hits the image sensor as soon as the photographer hits the shutter button.
Working of Digital Cameras
Mim I have found it! June 27, admin 0 Comments. Television with cathode ray tubes. February Learn how and when to remove this template message. The spectrofluorometer is an instrument which takes one advantage of fluorescent properties of some compounds in order to provide information regarding their concentration and chemical environment in vidicoon sample. If you are looking at an image the light bouncing off the object you are photographing, passes into the camera, through a set of lenses and onto a mirror. Would you like to merge this question into it?
Vidicon Camera Tube
Television Television is one of the marvels that has been achieved in the field of electronics. In sound broadcasting, sound waves are converted into equivalent electrical signals using microphone, which are modulated and transmitted. In picture broadcast television , the bright and dark spots of a scene are systematically scanned to produce equivalent electrical signals. These picture signals are modulated and are then transmitted. At the receiving end, the picture signals are extracted from the modulated wave. These are made to reproduce the bright and dark spots of the original scene on the fluorescent screen of a cathode ray tube called viewing tube. The sound associated with the scene is transmitted simultaneously to provide a complete picture and sound reproduction at the receiver.
What is Vidicon and its principal of working?