Golden Round Chafing Dish,Chafing Dish With Glass,Stainless Steel Chafing Dish,Oblong Chafing Dish Shaoxing Biaoyi Hardware Products Co., Ltd. , https://www.byeob.com
CCD (ChargeCoupledDevice), a "charge coupled device", in megapixels. How many megapixels in a digital camera specification refers to the resolution of the CCD. The CCD is a light-sensitive semiconductor chip used to capture graphics and is widely used in scanners, copiers, and filmless cameras. Similar to the principle of film, light passes through a lens and projects graphic information onto the CCD. But unlike film, CCD has neither the ability to record graphical data nor the ability to be permanently stored, or even "exposure" capabilities. All graphics data is sent to an "analog-to-digital" converter, a signal processor and a storage device (such as a memory chip or memory card). CCDs come in a variety of sizes and shapes, up to 2 x 2 square inches. 
CMOS (Complementary Metal Oxide Semiconductor), that is, "complementary metal oxide semiconductor". It is an important chip in a computer system, which preserves a large amount of data needed for system booting. CMOS sensors are easy to mass-produce, and they are fast and low-cost, which is one of the key development directions of digital cameras.
White Balance (WhiteBalance)
Under different light sources, the photos will be color cast due to different color temperatures. If the color temperature is low, the red light in the light, the yellow light content is more, the color of the photograph taken will be reddish, yellowish, the blue and green in the light when the color is high, the photos will be blue and green. At this time, it is necessary to use the white balance function for correction. The principle is to control the brightness of the red, green and blue tri-colors in the light, so that the maximum light position in the image reaches pure white, and the other colors can be made accurate.
Interpolation
A method of increasing the pixel size of an image without generating pixels, using a mathematical formula to calculate the color of the missing pixel based on the surrounding pixel color. Some cameras use interpolation to artificially increase the resolution of the image.
Bit (bit)
This is a term in computer images that describes the number of colors a generated image can contain. "Depth is 8 bits" means the image contains only 256 colors. Today's digital cameras have a color depth of 8 bits for each color. Since the color of each pixel is a mixture of red, green and blue colors, the image can contain 167×256×256 colors, which is called 24-bit color.
TWAIN
This is a very common word in digital photography. TWAIN is a special kind of software that allows other TWAIN-compliant software to share image resources. For example, PaintShopPro, which is a good shareware for image processing, works with TWAIN devices. So you can use the images in your digital camera directly in PaintShopPro. TWAIN devices include scanners, fax machines, and of course digital cameras.
Differentiate between CCD and CMOS
1970 was a milestone in the image processing industry, and Bell Labs invented the CCD. Twenty years later, people used this technology to make digital cameras, pushing the image processing industry to a whole new field. Digital cameras eliminate the need for film and rinsing, repeatable shooting and instant adjustment; images can be copied indefinitely without sacrificing quality for permanent storage and for electronic transfer and processing. Its birth has brought a revolution to the image processing industry.
Then, it was discovered that processing a chip in a computer system can also be used as a photosensitive sensor in a digital camera, that is, CMOS, which is convenient for mass production and low cost, and is a dream of the merchants. Industry insiders analyzed that it may replace CCD in the near future, and now both coexist. Many people think: "Photosensitive sensors, especially CCDs, are the most central component of the camera and the heart of digital cameras."
This is not the case: photosensitive sensors, especially CCDs, function in the camera to capture and convert light through the lens into an electronic signal, not so much the heart of a digital camera as the eye of a digital camera. In the research-grade camera, although the CCD or CMOS sensor is a very important component, it determines the pixel of the camera to a large extent, but the CCD/CMOS chip does not occupy the dominant position in the cost of the camera, especially in the The performance of this feature in the high-end field is more prominent.
From a technical point of view, CCD and CMOS have the following four differences:
Information reading method
The charge information stored by the CCD charge coupler needs to be read one bit after the synchronization signal control. The charge information transfer and the read output need to have a clock control circuit and three different sets of power supplies. The whole circuit is more complex. The CMOS photoelectric sensor directly generates a current (or voltage) signal after photoelectric conversion, and the signal reading is very simple.
speed
The CCD charge coupler needs to output information one bit at a time in the behavior unit under the control of the synchronous clock, and the speed is slow; while the CMOS photoelectric sensor can extract the electric signal and simultaneously process the image of each unit. Information, speed is much faster than CCD charge couplers.
Power and power consumption
CCD charge couplers mostly need three sets of power supply, which consumes a lot of power; CMOS photoelectric sensors only need to use one power supply, and the power consumption is very small, only 1/8 to 1/10 of CCD charge coupler, CMOS photoelectric sensor It has great advantages in energy saving.
Imaging quality
CCD charge coupler fabrication technology started early, the technology is mature, and the noise is isolated by PN junction or silicon dioxide (SiO2) isolation layer. The imaging quality has certain advantages over CMOS photoelectric sensors. Due to the high integration of CMOS photoelectric sensors, the distance between each photoelectric sensing element and circuit is very close, and the optical, electrical and magnetic interference between them is serious. The noise has a great influence on the image quality, making the CMOS photoelectric sensor for a long time. Unable to enter practical. In recent years, with the continuous development of CMOS circuit noise reduction technology, it has provided good conditions for the production of high-density and high-quality CMOS image sensors.
In addition, both CCD and CMOS sensors are different in "internal structure" and "external structure":
Internal structure (structure of the sensor itself)
The imaging points of the CCD are arranged in an X-Y vertical and horizontal matrix, and each imaging point consists of a photodiode and an adjacent charge storage area controlled by it. Photodiodes convert light (photons) into electric charges (electrons), and the amount of electrons collected is proportional to the intensity of the light. When these charges are read, each row of data is moved to a buffer in the direction of vertical charge transfer. The charge information for each row is continuously read and sensed by the charge/voltage converter and amplifier. The image produced by this configuration has the characteristics of low noise and high performance. However, the production of CCD requires a clock signal and a bias voltage technology, so the overall structure is complicated, which increases power consumption and increases cost.
Electronics around the CMOS sensor, such as digital logic, clock drivers, and analog-to-digital converters, can be integrated in the same processing program. The CMOS sensor is constructed like a memory, each imaging point contains a photodiode, a charge/voltage conversion unit, a reset and selection transistor, and an amplifier covering the entire sensor with a metal interconnect (chrono application and The read signal) and the longitudinally arranged output signal interconnects can be read by simple X-Y addressing techniques.
Introduction to the basics of digital cameras
[ Huaqiang Security Network News ] Detailed digital camera knowledge CMOS