Uploaded bySHASHI BHUSHAN
Viewing and recording the fluoroscopic image
The document describes the process of viewing and recording intensified fluoroscopic images. It discusses how an image intensifier converts visual light images into electrical signals that are then viewed on a video monitor or recorded. Recording can be done using spot film cameras, cinefluoroscopy movie cameras, or by recording the video signal from the television camera onto magnetic tape, discs, or optical discs. The television camera converts the light image back into an electrical video signal for viewing, storage, or transmission to other viewing locations.
More Related Content
Similar to Viewing and recording the fluoroscopic image
Viewing and recording the fluoroscopic image
- 1. VIEWING AND RECORDING OFTHE INTENSIFIED IMAGE Shashi Bhushan B Sc MIT (2nd Year)
- 2. Modern FluoroscopicUnit CINE ORPHOTOSPOT CAMERA SPOTFILM CASSETTE SLOT IMAGE INTENSIFIER VIDEO MONITOR PATIENT COUCH UNDER COUCH X RAY TUBE CONTROL KNOBS
- 3. INTENSIFICATION • Process ofbrightening the image. Visual information Electrical information Electrical information Visual information The apparatus used is the television camera
- 4.
- 5. TELEVISION CAMERA SIGNAL AMPLIFIER TVMONITOR (Viewing System) 1. Video/TV camera -Vidicon or Plumbicon -CCD 2. Video/TV Monitor 3. Digital RECORDING SYSTEM Cine film systems(Cinefluroscopy) Videotape recording Static spot filming systems VIDEO LINK
- 6. TELEVISION CAMERA COUPLING a)FIBRE OPTIC COUPLING b) OPTICAL LENS COUPLING
- 8. Because of thelimitations of the mirror optic viewing system, a more practical and efficient viewing system was employed. 1.Afford viewing by multiple persons. 2.Monitors may be located in remote locations other than the radiographic room. 3.Image brightness and contrast can be manipulated. 4.Images may be stored on different medium for reviewing at a later time.
- 9.
- 10. 1. Thermionic TVcamera tube • Works on principle of photoconductivity or photoemission. • Several types Vidicon Plumbicon Hivicon Chalnicon
- 11. Vidicon (tube) TVcamera
- 12. Parts of avidicon tube • Small electronic vacuum tube-1” in diameter & 6 in. in length. • Surrounded by coils- Electromagnetic focusing coil Electrostatic deflecting coils • Cathode-thermionic emission. • Control grid Accelerates electrons to the anode ELECTRON GUN
- 13. • Anode Extends acrossthe target end as a fine wire mesh. +ve potential of approx.250V with respect to the cathode. • Target assembly-3 layers GLASS FACE PLACE MAINTAIN VACCUM IN THE TUBE GLASS SIGNAL PLATE ELECTRICAL CONDUCTOR(25V) THIN TRANSPARENT FILM OF GRAPHITE TARGET PHOTOCONDUCTIVE ANTIMONY SULPHIDE GLOBULES IN MICA MATRIX
- 14.
- 15. Video signal formation Signalplate Glass face plate Target Globule Mica Photoelectron Light Electrical image Clipped signal Electron beam + ++ Video signal - - - -- - - - + ++
- 16.
- 17. 2. Ccd • Usevisible light to form an image • Silicon(photodiode) used as IC chip arranged in a matrix known as pixel. • The silicon surface of the CCD is photosensitive – as visible light falls on each pixel, electrons are liberated and build up in the pixel Electronic video signal to TV Monitor
- 18. ELECTRONS CAPTURED INCHARGE BUCKETS (STORED IMAGE) ELECTRONS PROPORTIONAL TO LIGHT INTENSITY FOCUSSED ON THE PHOTOELECTRIC CATHODE LIGHT PHOTONS
- 19.
- 20. VIDICON V/S Ccd *STORESNEGATIVE IMAGE *READ OUT BY THE CHARGE BUCKETS BEING MOVED FROM ONE BUCKET TO THE NEXT UNTIL THE CHARGE REACHES THE EDGE *SMALLER, REQUIRE LESS POWER, AND HAVE A LONGER LIFETIME. *STORES POSITIVE IMAGE *READ OUT BY ELECTRONIC BEAM
- 22. TV MONITOR • Lastlink in television chain. • Contains the picture tube & the controls regulating brightness and contrast. • Electron gun • Control grid • Anode focusing coil • Deflecting coil • Ion trap
- 23.
- 24. • Focusing anddeflecting coils control electron beam. • Brightness of individual dot is controlled by control grid. Receives video signal from camera control unit. Regulate no. of electrons in the beam. • Anode plated onto the inside surface of picture tube near the fluorescent screen. Carries higher +ve potential -10,000V • Electron strike fluorescent screen at the flared end-emit large no. of electrons-VISIBLE IMAGE
- 25. COLOR MONITOR • 3electron guns – one for each color • Screen not made up of continuous fluorescent material. Made up of alternating dots of three colors.
- 27.
- 28.
- 29. b). interlaced SCANNING VideoField Interlacing
- 31. 3. Digital Fluoroscopy •Image intensifier output screen coupled to TFTs • TFT photodiodes are connected to each pixel element • Resolution limited in favor of radiation exposure concerns
- 32.
- 33. RECORDING • Light imagefrom the Image Intensifier output phosphor. • Electronic signal from TV camera.
- 34. • Photo spotcamera • Cine camera Light image • Magnetic tape • Magnetic disc1.8GB • Optical disc50MB-6-8GB Electronic signal
- 35. 1. SPOT FILMRECORDER • X-ray film cassette interposed between x-ray beam & the image intensifier. • Exposure uses fluoroscopic kVp(80-90) and a higher mA 300-400. • Photo timer controls the length of exposure. PART POSITION EXPOSURE POSITION ¾ to 1sec delay
- 36. . SPOT FILMRECORDER
- 37. 2. PHOTOSPOT CAMERA •A spot film(Photospot) camera records the image o/p of Image Intensifier on a film. • Types : 105 mm & 70 mm camera using roll film. 100 mm camera using sheet film. • Capable of recording images at the rate of 1 per sec or rapid sequence of up to 12 per sec.
- 38.
- 39. Camera features • Separatesupply & take-up magazines. • Automatic exposure of patient data onto film. • Automatic recording of serial number of each shot in a sequence. • A safety mechanism to prevent use if camera runs empty or patient’s id card is not inserted.
- 41. 3. CINEFLUOROSCOPY • Processof recording images on movie(cine) film. • Beam splitting mirror allows cine recording. • Movie camera intercepts image – 16 mm and 35 mm formats – Record series of static exposures at high speed – 30 – 60 frames per second
- 43. Camera In Action •Filmtravel •Variable-speed motor •Shutter •Aperture
- 44. 44 3. Videotape(TV IMAGE)Recording • It involves recording the electrical signal from tv camera. • This group of recorders include: 1. Tape recorders 2. Magnetic disc recorders. 3. Optical disc recorders. • The three recorders may employ either analog or digital signals.
- 45. MAGNETIC TAPE RECORDERS MAGNETICDISC RECORDER OPTICAL DISC RECORDER
Editor's Notes
- #6 The video signal from pickup tube is very week and must be amplified before it can be used.once amplified, the video signal is fed through a screened cable to the TV monitor and also, perhaps, to a video recorder.
- #7 ‘Collimator lens:1st..function to render parallel the divergent light rays arriving frm o/p phosphor image….multielement lens combination –entry lens matched in diameter to o/p;exit lens much larger Camera or TV lens:is to focus the ll light beam frm collimator lens onto the signal plate of the TV pick up system or film in the fluorographic camera.