Question 2: What does the afterglow effect of oscilloscope mean? When the electron beam stops bombarding the fluorescent screen, the light spot can still be maintained for a certain time. This phenomenon is called "afterglow effect". Afterglow time includes short afterglow (0.0 1~0. 1s), medium afterglow (0. 1s) and long afterglow (less than 10-3s). When observing low-frequency signals, use oscilloscope tubes with long afterglow time; When observing high frequency signals, use oscilloscope tubes with short afterglow time.
Question 3: What is the function of oscilloscope afterglow mode? The fluorescence effect produced by the impact of electrons on the screen of analog oscilloscope gradually darkens with time until it disappears, which is the afterglow effect. So the waveform will stay on the screen for a period of time, and then gradually disappear, which is the afterglow time. The afterglow time directly affects the observation of the waveform. For example, if the afterglow time is too short, the user may miss some signals when blinking. To display data collected multiple times, you can use persistence. If the display afterglow is set, the oscilloscope can update the display with newly collected data, but the previously collected data will not be erased immediately. Previously collected data will be displayed with reduced brightness, while newly collected data will be displayed with normal color and brightness.
Question 4: What is the afterglow effect of LED? This is mainly the visual residual phenomenon of human eyes. I agree with the upstairs.
If you ask about the afterglow effect of LED, photons have been released after electron transition, which should not be produced without bombardment. If you insist, it can be understood that there are high-speed particles that have not yet hit, and will continue to move forward after the voltage drops, hitting the LED and causing the rear light to be released. ......
Question 5: Can plastic surgery be performed in plastic surgery hospitals? 10 transsexual surgery needs to go to a special hospital, and the general plastic surgery hospital can't do it!
Question 6: How to solve the afterglow effect of digital tube in single chip microcomputer? There are two possibilities: first, there is something wrong with your program, and the value sent to the same digital tube has changed during scanning.
Second, the hardware problem, the current is too large, or try another type of digital tube. I have done digital tube display on FPGA and single chip microcomputer, and I have never encountered such a problem.
Question 7: What does afterglow mean? Is the feeling of sunset.
Question 8: Explain the principle of visual persistence.
(Visual retention phenomenon, visual duration)
When the human eye observes the scene, it takes a short time for the optical signal to reach the brain nerve. After the light effect, the visual image did not disappear immediately. This residual vision is called "afterimage" and this visual phenomenon is called "visual persistence".
It is a phenomenon that the vision produced by light on the retina remains for a period of time after the light stops acting. Its specific application is shooting and projection. The reason is the reaction speed of the optic nerve, which lasts for a quarter of a second. It is the basis for the formation and dissemination of visual media such as animation and movies.
Vision actually depends on the lens imaging of the eyes. Photoreceptor cells are very sensitive to light, and light signals are converted into nerve currents, which are transmitted back to the brain to cause human vision. The photosensitivity of photoreceptor cells depends on some photosensitive pigments, and the formation of photosensitive pigments takes some time, forming a mechanism of visual pause.
The phenomenon of visual persistence was first discovered by China people. According to historical records, lanterns were the earliest application of visual persistence. There were lanterns in Song Dynasty, which were called "riding lanterns" at that time. Then the Frenchman Paul? Luo Gai invented the photographic disc in 1828, which is a disc with two sides crossed by ropes. One side of the plate is painted with a bird and the other side is painted with an empty cage. When the disc rotates, the bird appears in the cage. This proves that when the eye sees a series of images, it only keeps one image at a time.
When the object moves rapidly and the image seen by human eyes disappears, human eyes can still keep the image for about 0. 1-0.4 seconds. This phenomenon is called visual persistence. This is a characteristic of the human eye. When people look at an object, they image it on the retina and input it into the human brain through the optic nerve to feel the image of the object. However, when the object is removed, the imprint of the optic nerve on the object will not disappear immediately, but will last for 0. 1 -0.4 seconds. This characteristic of human eyes is called "visual persistence of eyes".