About the Subaru Telescope
Observational instruments
Suprime-Cam (Subaru Prime Focus Camera)

Suprime-Cam is an 80 megapixel, optical camera mounted at the Subaru Telescope's prime focus. Among large telescopes (6-10 m), it has the extraordinary capability not only to efficiently image a wide field of view, but also to capture very faint objects with high levels of detail and contrast in a single exposure. It is an ideal tool for: 1) surveying large areas of the distant Universe, particularly to study the birth and evolution of galaxies; 2) detecting small bodies on the outskirts of the Solar System, especially the Edgeworth-Kuiper Belt; and 3) mapping the distribution of dark matter in the Universe.
The name "Suprime" is a combination of "Subaru" and "Prime," referring to the Subaru Telescope's prime focus. It also alludes to the English word "supreme," reflecting the camera's outstanding performance and wide field of view.
Fast Facts
Description:
- Optical (visible-light) imager
- Wide field of view (about the size of a full moon)
- High spatial resolution of objects imaged
Operation:
- Images a wide field of view in a single exposure.
- Uses ultrasensitive CCDs to detect light collected in the 8.2 m primary mirror.
- Can use different color filters.
- Has a very fast survey speed.
Applications:
- Surveys of large areas of the Universe, particularly the far distant Universe
- Detection of faint objects in high spatial resolution
Specifics:
- Camera size and weight:
- 960 mm x 1035 mm (3.15 ft. x 3.4 ft.)
- 295 kg (650 lb.) alone and contained within a prime focus unit for a total weight of approximately 2 tons.
- Placement: prime focus within the top ring of the telescope
- Wavelength(s): visible range
- Detectors:
- Ten 2048 x 4096 pixel CCDs (charged-coupled devices), totalling 80 megapixels
- Arranged in a mosaic 5 x 2 pattern
- Pixel scale: 0.20 arcseconds
- Filters:
- Jukebox-type automatic filter exchange mechanism
- Maximum of 10 can be loaded in filter stacker, then used one at a time
- FOV: 34 x 27 arcminutes
- Corrector lens:
- Seven-element lens, 508 mm (20 in.) diameter
- Helps to ensure sharp images at prime focus
Development:
- Developers
- Collective development by the University of Tokyo (Graduate School of Science, Institute for Cosmic Ray Research) and the National Astronomical Observatory of Japan (NAOJ) from the 1980s, who faced the huge technological challenge of installing and balancing a big, heavy instrument at prime focus.
- Detectors:
- Original CCDs by MIT Lincoln Laboratory
- Current CCDs by Hamamatsu Photonics K.K.
- Corrector lens: Canon Inc.
- Web articles
