Introduction to the principle of three-dimensional waveform mapping of oscilloscopes
This article mainly discusses the principle of three-dimensional waveform mapping, combined with the ZDS oscilloscope to describe the meaning of grayscale display and color temperature display and the corresponding functions to help engineers deepen their understanding of the oscilloscope's waveform display and become more comfortable in the subsequent use of the oscilloscope.
The three-dimensional information of the waveform data includes: time, amplitude and number of amplitude hits. In the process of waveform processing by traditional DSO, the original data of the waveform is sampled to extract the data required for a waveform to draw, so that the sampling display only has time and amplitude information. In modern DSO, all the data collected after a trigger can be displayed on the screen, and the time, amplitude and number of hits of each amplitude of the waveform data can be reflected through a three-dimensional mapping grayscale image. For example, there are 14,000 sampling points in one trigger sampling, and there are 700 pixels in the horizontal direction of the DSO screen. In a traditional DSO, you only need to extract 1 sample point every 200 out of 14,000 sampling points, for a total of 700 pixels. pixels to represent the overall overview of the waveform. When performing three-dimensional waveform mapping, all 200 sample points will be compressed at one point in time and mapped to the three-dimensional database according to different amplitude values.
In order to convert the information in the three-dimensional waveform database into a display screen that is convenient for users to observe, the number of amplitude hits needs to be converted into waveform grayscale or color levels, so the three-dimensional waveform mapping model is essentially a three-dimensional waveform imaging technology. It directly maps each collected data to a three-dimensional database (grayscale image), and then transmits the grayscale image to the screen for display at a rate acceptable to the human eye.
Through the above principle introduction, we can know that the waveform of each screen in the oscilloscope is actually the superposition of several frames of sampled waveforms. In the normal display mode, the oscilloscope uses gray scale to represent the probability of the waveform appearing. The greater the probability of the waveform appearing, the brighter the color of the waveform. The smaller the probability of the waveform appearing, the darker the color of the waveform.
In addition, in order to facilitate users to more clearly observe the probability of waveform occurrence, ZDS series oscilloscopes are also equipped with a color temperature display function. In the color temperature display mode, the color temperature of the waveform is used to reflect the probability of the waveform appearing. Waveforms with a low frequency of occurrence are displayed in cool colors, and waveforms with a high frequency of occurrence are displayed in warm colors:
ZDS4000 oscilloscope has rich triggering methods, which can be triggered for different scenarios. By understanding the three-dimensional waveform mapping principle of the oscilloscope and combining it with the ZDS oscilloscope to describe the meaning of grayscale display and color temperature display, it can help engineers deepen their understanding of the oscilloscope's waveform display.
