The IBM 740 CRT Recorder was announced in 1954 and used with the

IBM 701 The IBM 701 Electronic Data Processing Machine, known as the Defense Calculator while in development, was IBM’s first commercial scientific computer and its first series production mainframe computer, which was announced to the public on May ...

IBM 704 The IBM 704 is a large digital mainframe computer introduced by IBM in 1954. It was the first mass-produced computer with hardware for floating-point arithmetic. The IBM 704 ''Manual of operation'' states: The type 704 Electronic Data-Proce ...

, and

IBM 709 The IBM 709 was a computer system, initially announced by IBM in January 1957 and first installed during August 1958. The 709 was an improved version of its predecessor, the IBM 704, and was the third of the IBM 700/7000 series of scientific co ...

computer A computer is a machine that can be programmed to carry out sequences of arithmetic or logical operations ( computation) automatically. Modern digital electronic computers can perform generic sets of operations known as programs. These prog ...

s to draw

vector graphics Vector graphics is a form of computer graphics in which visual images are created directly from geometric shapes defined on a Cartesian plane, such as points, lines, curves and polygons. The associated mechanisms may include vector display ...

images, point by point, on 35 mm

photographic film Photographic film is a strip or sheet of transparent film base coated on one side with a gelatin emulsion containing microscopically small light-sensitive silver halide crystals. The sizes and other characteristics of the crystals determine ...

(i.e.

microfilm Microforms are scaled-down reproductions of documents, typically either films or paper, made for the purposes of transmission, storage, reading, and printing. Microform images are commonly reduced to about 4% or of the original document size. ...

). The 740

film recorder A film recorder is a graphical output device for transferring images to photographic film from a digital source. In a typical film recorder, an image is passed from a host computer to a mechanism to expose film through a variety of methods, h ...

contained

digital-to-analog converter In electronics, a digital-to-analog converter (DAC, D/A, D2A, or D-to-A) is a system that converts a digital signal into an analog signal. An analog-to-digital converter (ADC) performs the reverse function. There are several DAC archit ...

s and a 7-inch, high precision,

electrostatic Electrostatics is a branch of physics that studies electric charges at rest ( static electricity). Since classical times, it has been known that some materials, such as amber, attract lightweight particles after rubbing. The Greek word for ...

CRT. The raster size was 1,024 by 1,024, but only 256 resolved spots could be displayed on a vertical or horizontal line. Points could be displayed in one of two intensities, and a line could be drawn from a point, vertically or horizontally, to the edge of the display to form an axis. Each point to be displayed was stored in a single 36 bit word, with 10 bits each for the X and Y coordinates, and 3 control bits, one to set either high or low intensity and two to indicate that an X or Y axis is to be drawn starting from the given point. If both the X and Y axis bits were set, a 45 degree line was drawn. The 740's CRT used a short persistence ''P11''

phosphor A phosphor is a substance that exhibits the phenomenon of luminescence; it emits light when exposed to some type of radiant energy. The term is used both for fluorescent or phosphorescent substances which glow on exposure to ultraviolet or v ...

. The film used was 35 mm and was stored in a magazine that could hold up to 100 feet. ASA 200 speed film was recommended. The film could be advanced under computer control. The IBM 780 CRT Display was a monitor that could be attached to the 740 and mirror to an operator what was being drawn on 740's CRT. The 780 had a 21-inch CRT with a longer persistence (2 second, nominal) ''P7'' phosphor.

References

* IBM 709 Data Processing System, Form A22-6501-0, 1958, p. 106ff.
IBM Archive article about the 740

External links

CRT Phosphor Characteristics

740 __NOTOC__ Year 740 ( DCCXL) was a leap year starting on Friday (link will display the full calendar) of the Julian calendar, the 740th year of the Common Era (CE) and ''Anno Domini'' (AD) designations, the 740th year of the 1st millennium, th ...

Display 740 History of human–computer interaction {{compu-graphics-stub

See also

References

External links