数码相机关于DDC大小怎样选择？英文双语对照

说到CCD的尺寸，其实是说感光器件的面积大小，这里就包括了CCD和CMOS。感光器件的面积大小，CCD/CMOS面积越大，捕获的光子越多，感光性能越好，信噪比越低。CCD/CMOS是数码相机用来感光成像的部件，相当于光学传统相机中的胶卷。 　　CCD上感光组件的表面具有储存电荷的能力，并以矩阵的方式排列。当其表面感受到光线时，会将电荷反应在组件上，整个CCD上的所有感光组件所产生的信号，就构成了一个完整的画面。 　　如果分解CCD，你会发现CCD的结构为三层，第一层是“微型镜头”，第二层是“分色滤色片”以及第三层“感光层”。 　　第一层“微型镜头” 　　我们知道，数码相机成像的关键是在于其感光层，为了扩展CCD的采光率，必须扩展单一像素的受光面积。但是提高采光率的办法也容易使画质下降。这一层“微型镜头”就等于在感光层前面加上一副眼镜。因此感光面积不再因为传感器的开口面积而决定，而改由微型镜片的表面积来决定。 　　第二层是“分色滤色片” 　　CCD的第二层是“分色滤色片”，目前有两种分色方式，一是RGB原色分色法，另一个则是CMYK补色分色法这两种方法各有优缺点。首先，我们先了解一下两种分色法的概念，RGB即三原色分色法，几乎所有人类眼镜可以识别的颜色，都可以通过红、绿和蓝来组成，而RGB三个字母分别就是Red,Green和Blue，这说明RGB分色法是通过这三个通道的颜色调节而成。再说CMYK，这是由四个通道的颜色配合而成，他们分别是青（C）、洋红(M)、黄(Y)、黑(K)。在印刷业中，CMYK更为适用，但其调节出来的颜色不及RGB的多。 　　原色CCD的优势在于画质锐利，色彩真实，但缺点则是噪声问题。因此，大家可以注意，一般采用原色CCD的数码相机，在ISO感光度上多半不会超过400。相对的，补色CCD多了一个Y黄色滤色器，在色彩的分辨上比较仔细，但却牺牲了部分影像的分辨率，而在ISO值上，补色CCD可以容忍较高的感光度，一般都可设定在800以上 　　第三层：感光层 　　CCD的第三层是“感光片”，这层主要是负责将穿过滤色层的光源转换成电子信号，并将信号传送到影像处理芯片，将影像还原。 　　传统的照相机胶卷尺寸为35mm，35mm为对角长度，35mm胶卷的感光面积为36x24mm。换算到数码相机，对角长度约接近35mm的，CCD/CMOS尺寸越大。在单反数码相机中，很多都拥有接近35mm的CCD/CMOS尺寸，例如尼康德D100，CCD/CMOS尺寸面积达到23.7x15.6，比起消费级数码相机要大很多，而佳能的EOS-1Ds的CMOS尺寸为36x24mm，达到了35mm的面积，所以成像也相对较好。 　　现在市面上的消费级数码相机主要有2/3英寸、1/1.8英寸、1/2.7英寸、1/3.2英寸四种。CCD/CMOS尺寸越大，感光面积越大，成像效果越好。1/1.8英寸的300万像素相机效果通常好于1/2.7英寸的400万像素相机(后者的感光面积只有前者的55%)。而相同尺寸的CCD/CMOS像素增加固然是件好事，但这也会导致单个像素的感光面积缩小，有曝光不足的可能。但如果在增加CCD/CMOS像素的同时想维持现有的图像质量，就必须在至少维持单个像素面积不减小的基础上增大CCD/CMOS的总面积。目前更大尺寸CCD/CMOS加工制造比较困难，成本也非常高。因此，CCD/CMOS尺寸较大的数码相机，价格也较高。感光器件的大小直接影响数码相机的体积重量。超薄、超轻的数码相机一般CCD/CMOS尺寸也小，而越专业的数码相机，CCD/CMOS尺寸也越大。

The dimension of respecting CCD, it is the area size that says sensitive parts of an apparatus actually, here included CCD and CMOS. The area size of sensitive parts of an apparatus, CCD/CMOS area is larger, captured photon is more, sensitive performance is better, letter a confusion of voices is lower than jumping over. CCD/CMOS is digital camera uses sensitization to become the part that resemble, be equivalent to film of optical and traditional magazine. The surface of sensitive component on CCD is had store the ability of charge, arrange with the means of matrix. When its surface experiences the light, reaction of meeting general charge is on package, the signal that all sensitive component place on whole CCD generate, made a complete appearance. If decompose CCD, you can discover the structure of CCD is three-layer, ground floor is " miniature camera lens " , the 2nd is " color separation colour filter " with three-layer of pass an imperial examination " photosensitive layer " . Ground floor " miniature camera lens " we know 　 , digital camera becomes the key that resemble is to depend on its photosensitive layer, to expand the daylighting of CCD is led, must expand onefold the area getting light that resembles element. But the idea that raises daylighting rate makes the picture drops character easily also. This one " miniature camera lens " be equal to on one pair of glasses is added in front of photosensitive layer. Because this is sensitive,the area decides because of the mouth area of sensor no longer, and change to be decided by the watch area of miniature lens. The 2nd is " color separation colour filter " it is the 2nd of 　 　 CCD " color separation colour filter " , have kind of two kinds of color separation at present, it is law of RGB unbleached color separation, another is law of color separation of CMYK complementary color these two kinds of methods have actor drawback each. Above all, we understand the concept of law of two kinds of color separation first, RGB namely law of 3 unbleached color separation, glasses of almost all mankind can remember other facial expression, can pass red, green and blue will comprise, and RGB3 the letter is Red respectively, green and Blue, the color that this shows to law of RGB color separation is to carry these 3 channels adjusts and become. Say CMYK again, this is be cooperated by the color of 4 passageways and become, they are green respectively (C) , kermes (M) , yellow (Y) , black (K) . In print, CMYK is more applicable, but its adjust the color that come out not as good as many of RGB. The advantage of unbleached CCD depends on a picture pledging keen, colour is true, but defect is noise problem. Accordingly, everybody can notice, introduce the digital camera of unbleached CCD commonly, on ISO speed most won't exceed 400. Opposite, complementary color CCD became much color of filter of yellow of a Y implement, more careful on colorific resolution, but sacrificed however the resolution with video part, and go up in ISO value, complementary color CCD can tolerate higher speed, general but set is in three-layer of 800 above 　 : The three-layer of CCD of 　 of photosensitive layer 　 is " plate " , this basically is to be in charge of will crossing the illuminant of filter lubricious layer to be changed into electronic signal, convey signal video processing chip, will video reductive. Traditional camera film measure is 35mm, 35mm is diagonally length, the sensitive area of 35mm film is 36x24mm. Conversion arrives digital camera, diagonally length is close to 35mm about, CCD/CMOS size is larger. Digital camera is turned over in sheet in, a lot of have the CCD/CMOS measure that is close to 35mm, for example Ni Kangde D100, CCD/CMOS dimension area achieves 23.7x15.6, compared with consumption level number camera wants a lot of bigger, and beautiful can the CMOS dimension of EOS-1Ds is 36x24mm, reached the area of 35mm, become so picture opposite also better. The camera of consumptive level number on market basically has 2/3 now inch, 1/1.8 inch, 1/2.7 inch, 1/3.2 inch 4 kinds. CCD/CMOS size is larger, sensitive area is larger, it is better like the effect to become. 1/1.8 inch effect of 3 million camera resembling element normally good at 1/2.7 inch 4 million camera resembling element (latter sensitive area has former 55%) only. And the CCD/CMOS of same size increases like element is a favour admittedly, but this also can be brought about individual the sensitive area that resembles element is contractible, have the possibility of underexposure. But if increasing,want to maintain existing picture quality, with respect to the gross area that CCD/CMOS increases on the base that must preserving individual area resembling element to be not reduced at least. It is more difficult that at present treatment of larger size CCD/CMOS is made, cost is very high also. Accordingly, the digital watch for an opportunity with CCD/CMOS greater dimension, the price is higher also. The size of sensitive parts of an apparatus affects the bulk weight of digital camera directly. Ultrathin, exceed small digital camera general CCD/CMOS size is small also, and more professional number camera, CCD/CMOS size is larger also.