QHYCCD QHY5III485C Color

QHY5III485C uses Sony’s new IMX485, back-illuminated, 8.4 megapixel color CMOS sensor with an array of 3864 x 2180 pixels at 2.9um. With USB 3.0 interface, the full frame rate of 44 FPS at 8-bits or 18.5 FPS at 16-bits. Smaller regions of interest will yield even faster frame rates.

The resolution of QHY5III485C is 16:9, which is equivalent to the mainstream video output ratio. With the native high resolution, 485C can play a special role in recording astronomical video and astronomical science live broadcast.

QHY5III485C is specially equipped with 128MB DDR bulid-in image buffer. In non-video output mode, DDR built-in buffer can effectively relieve the transmission pressure brought by high-resolution large data volume and reduce information loss.

Back Illumination

One benefit of the back-illuminated CMOS structure is improved full well capacity. In a typical front-illuminated sensor, photons from the target entering the photosensitive layer of the sensor must first pass through the metal wiring that is embedded just above the photosensitive layer. The wiring structure reflects some of the photons and reduces the efficiency of the sensor.

In the back- illuminated sensor the light is allowed to enter the photosensitive surface from the reverse side. In this case the sensor’s embedded wiring structure is below the photosensitive layer. As a result, more incoming photons strike the photosensitive layer and more electrons are generated and captured in the pixel well. This ratio of photon to electron production is called quantum efficiency. The higher the quantum efficiency the more efficient the sensor is at converting photons to electrons and hence the more sensitive the sensor is to capturing an image of something dim.

AllSky Applications

The QHY5III485C standard package includes a 2.5mm Fisheye lens that converts the planetary camera into a high-resolution, 8.4 Megapixel All Sky camera with 180-degree field of view.