Canon 5D Mark III sensor kill / 5D Mark III grillé au capteur à cause d'un laser
Explanation and a thought by an applied physicist: The CMOS video sensor in this camera captures voltages from a row of photodetectors at a time (each 1/60s). The photodetecters (operating in photovoltaic mode) transduce a group signal output charge (collected from photons incident on each pixel) during the integration time, which is (1/60)(e) seconds = approx. 0.045 sec. Light from a green laser has a "short" wavelength (~532 nm) and shorter wavelengths are absorbed in the first few microns of the photosensitive region of a CMOS. A Class IIIb laser will emit 4.6 x 10^18 photons per second, so the number of photons incident on a pixel in a second must be LESS THAN (5 x 10^18 photons/s)(0.045 sec)(3.14 x 3.0625 mm^2) / (28.7 mm x 19.1 mm)(8,200,000 pixel/mm^2) = 4.8 x 10^8 photons in the case of direct and constant illumination of the CMOS. The laser source has a diameter of 3.5 mm at a distance of 10m with a divergence angle of 0.17 mrad, so at a distance of 50m from each CMOS pixel, its diameter would be 8.7 mm (area = 3.14 x (4.35 mm)^2 = 59.4 mm^2). The CMOS in this example is constructed such that 70% of the area of each photodiode is optically opaque or reflective (shielded by transistors and metallic bus circuitry) so the max number of photons incident on a pixel in this case is about 2.3 x 10^7 which is not enough to melt copper. 2.3 x 10^7 photons will, however, excite copper electrons just enough to raise the temperature along a single analog->digital converter to disrupt the layer of tantalum nitride that gates (constrains) electromagnetic propagation along copper wires through a column bus, creating a logic non-function scenario (constant "open" voltage signal to MOSFETs along the bus) that causes the "gate noise" we can see as a red horizontal line. This line will be evident in all future images captured by this CMOS. Although the light made a physical change, destroying circuitry, it just as true that that laser "overcommunicated" with a logical circuit such that a passive information receptor became overloaded, killing the component by information density (or entropic brute force!) Most will not fully comprehend the implications of the previous sentence.
パワーステアリングの部品に不具合が出て生産を停止してる模様？
今日の午後・・・・毎度のディズニーシーへ出向く予定が？
ここ最近購入したレプリカ用スクリーン・・・・
ここ数ヶ月バイクよりも自転車の修繕が多くなった。
この程・・・・ディスコなどで強烈な光でカメラのセンサーが・・・・
