History of the Oscilloscope: Visualizing with Light, the CRT, to the Modern Oscilloscope

在this third part to our series, we cover the most recent history of the oscilloscope up to modern times.

在几乎所有使用电子的研讨会或实验室中都发现，许多人可能会认为所有这些都将示波器置于现有的情况下。这次旅程很有趣，并以许多意外发现和奇怪的观察达到了顶峰。

Here is the third and final part in a series of the history of the oscilloscope, describing the evolution of the oscillograph using light, the invention of the cathode ray tube, to the form we are familiar with today.

You can check out the first two parts of this series here:

• 琥珀和青蛙腿
• Oersted’s Laws and Hand Drawn Waveforms

Visualizing with Light: Photographic and Mirror Waveforms

在part 2，我们了解了由法国物理学家Édouard医院发明的Hospitionier onexograph自动化一部分波形开发过程的发展。尽管本发明设法加快了该过程的一部分，但仍然涉及大量劳动力，但仍然缺乏精度，并且受信号频率的限制。这仍然是对正在测量的波形的间接测量，并且不是实时发生的。

移动线圈振荡器的发明是更接近实时，准确的波形测量的一步。该设备是由英国工程师威廉·达德尔（William Duddell）在1900年代初发明的，它是通过旋转悬挂在油中并暴露于测量电流的磁场的镜子来工作的。镜子将根据该电流的方向和强度旋转，并将光束反射到照相滑梯上以记录梁。这使记录较高频率的信号成为可能。

还有一个障碍提供真实的-time measurements, since the photographs had to be developed, but simplified the process significantly.

在vention of the Cathode Ray Tube and Commercial Adoption

The development and subsequent commercialization of the cathode ray tube (CRT) would lead to the first early oscilloscopes. The CRT oscilloscope began as an experimental instrument invented by German physicist, Karl Ferdinand Braun in the late 1800s, and provided insight into the behavior of electrons. Charged deflector plates would deflect electron beams onto a phosphorous coated surface, giving immediate visual insight.

The concept would be further developed and used in commercial equipment in 1932 by A. C. Cossor, a British company that would eventually become Raytheon. The CRT oscilloscope was widely used during World War II, and variations were made using different phosphorescent materials. This material had an impact on the intensity of the visualized signal, and how long it took to fade. Some materials would be more suitable for single trigger or low-frequency waveforms, which would fade more slowly and be visible for longer, for example.

These CRT oscilloscopes were initially not very accurate for measurement, but were great at providing insight into electrical system behaviors.

The A.C. Cossor 1035 MKIII CRT display oscilloscope, released in 1950. Image courtesy ofRichard Sears.

频率触发器和时间触发器

在the 1930s, another company gained significant momentum in oscilloscope development. DuMont began selling the DuMont 164 oscilloscope in 1939, and invented the first frequency trigger and sweep oscilloscope, the Model 224-A.

Shortly after the war, in 1946, Tektronix, Inc. was founded. One of the four founders, Howard Vollum, invented the first time based triggered oscilloscope known as the Tektronix Type 511. Vollum was motivated to develop a device that could provide quantitative measurements. The calibrated, CRT based 511 would weigh 65lbs, consume 180 W, and retail for $795USD in 1947 (equivalent to just under $10,000 in 2019). It had a frequency range of 10 Hz-10 MHz.

Tektronix将继续在示波器领域进行创新，从1947年的12名员工成长到1952年的359名员工。

Tektronix类型511示波器。图像提供W140.

固态到数字

从1940年代到1970年代的剩余时间里，其他几家公司也将在包括惠普（Hewlett-Packard）和勒克罗伊（Lecroy）在内的市场上吸引。惠普（Hewlett-Packard）将于1969年推出HP 1200A，这是第一个完全固态示波器示波器，其带宽为500kHz。

虽然数字示波器的发明可以归功于Tektronix，但由于工程师Hiro Moriyasu，Lecroy将通过在1971年释放WD 2000（一种实时的数字示波器）来击败他们。WD 2000的记忆力为20个样本，采样率为1 ns。

HP would be the first company to sell a fully digital, microprocessor-based oscilloscope: the HP 1980A/B.

HP 1980a。图像提供HP Memory Project.

当今的示波器技术

It can be hard to keep up with the innovations that continue to occur in the oscilloscope domain today. What is certain is that in the decades between the 1930s and 1980s, oscilloscopes rapidly became more precise, faster, portable, and affordable.

在novations today range quite significantly, from increased bandwidth, channels, decreased size and power, or even combining multiple tools into one device (such as the case with the MDO300 Tektronix series, which is a 6-in-1 oscilloscope/digital multimeter/spectrum analyzer/logic analyzer/protocol analyzer/arbitrary signal generator). There are even devices like the Pokit meter which pairs with a user’s smartphone to provide oscilloscope function.

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Measuring electricity and understanding the phenomenon has been a long journey. Electricity was a poorly understood force, and initial measurements of it were crude. Advancements in several fields had to occur before the oscilloscope was possible: general physics knowledge of electricity, the link between electricity and magnetism, tools to automate measurement collection, and then eventually the CRT.

感谢您在这个系列中坚持我们！如果您有兴趣了解其他有关其他历史设备或工程师的信息，请在下面的评论中告诉我们。

特色图像由Krzysztof Kamil.