OPPO shows optical zoom with 85-200mm equivalent for smartphones
OPPO is working on a periscopic optical zoom lens with moving parts for smartphones. The zoom lens has a range equivalent to 85-200mm on a full-frame camera. OPPO also shows five-axis image stabilization for smartphones.
OPPO speaks of ‘continuous optical zoom’, referring to the fact that the 85-200mm lens is actually a zoom lens with different focal lengths. The Chinese manufacturer uses a periscopic construction for this, in which the lens lies flat in the phone and the sensor is at an angle. The light enters the phone through a prism.
Current ‘zoom lenses’ on smartphones are almost always telephoto lenses with a fixed focal length. For example, in marketing terms, manufacturers talk about or 5x ‘optical zoom’, if the focal length of that telephoto lens is 5x longer than that of the primary camera.
In comparison, the 85-200mm zoom lens would offer a maximum of about 8x ‘optical zoom’. Phones’ primary camera usually has around the equivalent of a 24mm to 28mm lens. The zoom range of the 85-200mm is in fact 2.3x, because that is determined by the ratio between the longest and shortest focal length.
OPPO says it uses a lens construction made of glass and plastic, with “ultra-thin aspherical lenses”, which should ensure good image quality. When the zoom lens comes to smartphones is not yet known. VIVO already showed a concept smartphone with an optical zoom lens last year. With the Xperia 1 III, Sony already has a camera with a telephoto lens that can switch between two focal lengths, namely 75 and 105mm.
Five-axis image stabilization
OPPO also demonstrates its Five-axis OIS technology. That five-axis image stabilization uses the gyroscope to detect movement. Both the lens and the image sensor can move to compensate for that movement over five axes. The optical stabilization of the lens is used for small movements and the sensor shift is also used for larger movements.
OPPO claims that this allows a maximum stabilization angle of 3 degrees and that this is three times more than other image stabilization techniques in smartphones. From the beginning of next year, OPPO will use the technology in smartphones.
New rgbw sensor and camera behind the screen
OPPO also shows a new version of an RGBW sensor, a sensor with an extra white subpixel, which should improve light sensitivity. OPPO claims that the new sensor generates up to 35 percent less noise. The manufacturer says nothing about the dimensions of the sensor. The new sensor will come to OPPO phones at the end of this year. Some phone cameras have already modified the pixel layout to boost light sensitivity. For example, Sony sensors in Huawei phones have exchanged the green subpixels for yellow ones. Huawei has been using those sensors for several years. Before that, Huawei already used rgbw sensors, including in its P8 smartphone.
OPPO is also showing off its improved behind-the-screen camera tech, which it announced earlier this month. The manufacturer now says it can make screens with a pixel density of 400ppi where the camera is located. That’s similar to what Xiaomi and ZTE claim with their latest generations of cameras behind the front screen. Due to this high pixel density, the place where the camera is located is less noticeable, because the pixel density is the same as that of the rest of the screen. OPPO showed off the new techniques at its Future Imaging event.