The SXF frame store.

General:

The frame store consists of a 262,144 x 16 bit static RAM, with its input derived from a high speed 12 bit A-D converter and double-sampling correlator. The correlator processes the camera output and minimises the electronic noise before conversion to digital form and storage in the RAM. A complete 130,560 pixel image is downloaded from the camera and stored in the static RAM in approximately 1.5 seconds. Once in the memory, an 8 bit video D-A converter is used to display the contents on a TV monitor screen, the video being a standard 1 volt PAL or NTSC signal taken out via a BNC socket on the rear of the frame store box. The image data in the memory is also accessible via an 8-bit wide computer interface port on the front panel. This port can be interrogated by any PC fitted with a Starlight Xpress card (provided with the system), or via a printer port interface module (optional). The rest of the frame store consists of a switch-mode power supply, capable of operating from 240V or 115V AC, or from 12V DC, and the memory control circuitry required to read the camera and display the stored images.

• Memory capacity: 262,144 x 16 bits - capable of holding two 512 x 256 pixel images or one 512 x 512 pixel 16 bit image.
• D-A converter: 12 bit, 2.7 microseconds per pixel max. conversion rate.
• Camera readout speed: Approx. 80,000 pixels per second (1.5 seconds to read the SX camera).
• Camera cooling: Regulated TE cooler supply with -10C and -20C set points. Regulation to within +/- 0.5C max. deviation.
• Power requirements: 240VAC/ 115VAC @ 30VA, or 12VDC @ 3A max.
• Video output: 1 volt p-p into 75 ohms, CCIR (European standard) or EIA (US standard) pre-set at manufacture, 256 grey levels.
• Computer interface: 8 bit wide bi-directional data port. Data transfer rate 8 MHz max. via a 700mm ribbon cable and PC expansion card or parallel printer port module.
• Size: Black/ grey aluminium case, 380 x 240 x 65mm.

The SXF camera.

The standard monochrome camera for use with the SX frame store has the following specification:

• CCD: Sony ICX027BL-6 Hyper -HAD interline transfer CCD with on-chip microlenses.
• Active area: 6.4 x 4.3mm
• Active pixels: 500 x 256
• Pixel size: 12.4 (h) x 16.6 (v) microns
• Full well depth: Approx. 80,000e
• Anti-blooming spec: Greater than 1000x overload
• Dark signal: Less than 1e / second at -20C
• Electronic shutter speed: Less than 2.5 microseconds operating time
• Spectral response: Peak response at 550nM (Green), 50% at 420nM (Blue) and 720nM (Red)

Camera mechanical details:

• Cooling: Two stage thermoelectric cooler, capable of sustaining a -45C temperature differential between the CCD and heatsink. See frame store spec.
• Size: 100mm diameter, 90mm front to back.
• Optical interface: M42 x 1mm internally threaded barrel with screw-in 32mm (1.25 inch) push fit drawtube adaptor. Will take a standard 'Pentax' thread lens.
• Back focus distance: Barrel front face to CCD distance is approximately 28mm.
• Connecting cable:
• Cable size: Approximately 9mm diameter, terminated with 25 way 'D' style connectors