Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
  • H01J29/00—Details of cathode-ray tubes or of electron-beam tubes of the types covered by group H01J31/00
  • H01J29/02—Electrodes; Screens; Mounting, supporting, spacing or insulating thereof
  • H01J29/10—Screens on or from which an image or pattern is formed, picked up, converted or stored
  • H01J29/18—Luminescent screens
  • H01J29/30—Luminescent screens with luminescent material discontinuously arranged, e.g. in dots, in lines
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
  • G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
  • G01S7/04—Display arrangements
  • G01S7/06—Cathode-ray tube displays or other two dimensional or three-dimensional displays
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
  • G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
  • G01S7/04—Display arrangements
  • G01S7/06—Cathode-ray tube displays or other two dimensional or three-dimensional displays
  • G01S7/22—Producing cursor lines and indicia by electronic means

Definitions

• the invention refers to a cathode ray tube (CRT) for simultaneously displaying graphic and alphanumeric information.
• CTR cathode ray tube
• Computer systems for processing position information from radar monitoring equipment are often used for controlling and guiding air and maritime traffic. Furthermore, other kinds of information, such as route, arrival time, collision risk etc., are collected and processed. All this information is displayed to traffic controlles who, with the aid of it, control traffic in progress.
• the radar images which are displayed are reproduced at a frequency corresponding to the rotational speed of the radar scanner, which is normally of the magnitude of one revolution per second.
• the requirement for obtaining an acceptable display of the radar scans is that the CRT display persistence time is long. This long persistence time is a disadvantage when displaying alphanumeric information. When such information is changed the display will be blurred, due to the persistence time. Furthermore, the fluorescent coating will be destroyed if stationary information is continuously displayed. To avoid these problems the radar information is generally displayed on one CRT having a long persistence time, while the alphanumeric information is displayed on another CRT having a short perisistence time. This solution, however, is both expensive and voluminous.
• the invention relates to a CRT, which solves the aforementioned problems with simultaneously displaying the graphic and alphanumeric information. This is done by the screen of the CRT being provided with one zone having a short, and another zone having a long persistence time.
• the characterizing features of the invention are disclosed in claims 1 and 2.
• Figure 1 illustrates a display screen in accordance with the invention displaying radar image and alphanumeric information.
• a radar image of an airplane in the air is desplayed in the upper zone A of the screen.
• Superposed on the radar image there is displayed a computer-generated image.
• the latter is a stylized map of the area in question, airplane identification symbols etc.
• This zone A is provided with a fluorescent coating 1 of a material with the commercial denotation P26, this coating having a persistence time of about 50 seconds. Persistence time is defined as the time it takes for luminescence to deteriorate to 5% of its initial value.
• a computer-generated alphanumeric image is displayed in the lower zone B of the screen. It may, for example, contain information as to the route, calculated arrival time etc for different airplanes.
• This zone B of the screen is provided with a fluorescent coating 2 with the commercial denotation P39. This coating has a persistence time of about two seconds.
• Figure 2 illustrates the screen in length section, where the front glass 3 of the screen is provided with a fluorescent coating 1 of the material P26 over one part of its surface, and with a coating of the material P39 over another part of its surface.

Landscapes

• Engineering & Computer Science (AREA)
• Computer Networks & Wireless Communication (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Radar, Positioning & Navigation (AREA)
• Remote Sensing (AREA)
• Radar Systems Or Details Thereof (AREA)
• Illuminated Signs And Luminous Advertising (AREA)
• Devices For Indicating Variable Information By Combining Individual Elements (AREA)
• Overhead Projectors And Projection Screens (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=20349938

Family Applications (1)

Country Status (6)

Families Citing this family (2)

Family Cites Families (3)

• 1983
  • 1983-02-09 SE SE8300656A patent/SE435331B/sv not_active Application Discontinuation
• 1984
  • 1984-02-01 WO PCT/SE1984/000030 patent/WO1984003174A1/en not_active Ceased
  • 1984-02-01 JP JP59500783A patent/JPS60500431A/ja active Pending
  • 1984-02-01 EP EP84900762A patent/EP0136304A1/en not_active Withdrawn
  • 1984-02-08 IT IT8419507A patent/IT8419507A0/it unknown
  • 1984-10-05 DK DK479484A patent/DK479484D0/da not_active Application Discontinuation

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events