Single-lens translucent (SLT) is a

Sony , commonly stylized as SONY, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan. As a major technology company, it operates as one of the world's largest manufacturers of consumer and professiona ...

proprietary designation for

Sony Alpha , commonly stylized as SONY, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan. As a major technology company, it operates as one of the world's largest manufacturers of consumer and professional ...

cameras which employ a pellicle mirror,

electronic viewfinder An electronic viewfinder (EVF) is a camera viewfinder where the image captured by the lens is displayed on a small screen (usually LCD or OLED) which the photographer can look through when composing their shot. It differs from a live preview ...

, and phase-detection autofocus system. They employ the same Minolta A-mount as Sony Alpha DSLR cameras. Sony SLT cameras have a semi-transparent fixed mirror which diverts a portion of incoming light to a phase-detection autofocus sensor, while the remaining light strikes a

digital image sensor An image sensor or imager is a sensor that detects and conveys information used to make an image. It does so by converting the variable attenuation of light waves (as they refraction, pass through or reflection (physics), reflect off objects) in ...

. The image sensor feeds the electronic viewfinder, and also records still images and video on command. The utility of the SLT design is to allow full-time phase-detection autofocus during electronic viewfinder, live view, and video recording operation. With the advent of digital image sensors with integrated phase-detection, the SLT design is no longer required to accomplish this goal, as evidenced by cameras such as the Sony NEX-5R, Fujifilm X-100s, and Nikon 1, although the SLT design avoids having pixels unavailable for image formation due to their space on the sensor being occupied by a dedicated phase detection autofocus sensor. The term "

translucent In the field of optics, transparency (also called pellucidity or diaphaneity) is the physical property of allowing light to pass through the material without appreciable scattering of light. On a macroscopic scale (one in which the dimensions ...

" is a misnomer for the actual SLT design, which employs a pellicle mirror that is not translucent. Pellicle mirrors have been used in single-lens reflex cameras from at least the 1960s (see Canon Pellix) and in the Pentax EI2000/Hewlett Packard 912 digital SLR of 2000 which used an optical viewfinder and on-sensor contrast-detection focussing.

List of SLT cameras

All of the above cameras record 1920x1080 video at 60i/30p (NTSC regions) or 50i/25p (PAL regions), in MPEG-4,

AVCHD AVCHD (Advanced Video Coding High Definition) is a file-based format for the digital recording and playback of high-definition video. It is H.264 and Dolby AC-3 packaged into the MPEG transport stream, with a set of constraints designed around t ...

H.264 Advanced Video Coding (AVC), also referred to as H.264 or MPEG-4 Part 10, is a video compression standard based on block-oriented, motion-compensated coding. It is by far the most commonly used format for the recording, compression, and distr ...

formats. The Alpha 65 and 77 also records video at 50p or 60p, and the Alpha 99II records 4k video at 100Mbit/s (using XAVC S) with full sensor read-out. Source: summarised from th
full comparison table at DP Review

References

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List of SLT cameras

See also

References