If you have ever come across Logitech’s Performance Mouse MX or the Anywhere Mouse MX, you would have noticed that these mice are different from any other computer mice you have ever used… they can be used on transparent glass. Where lesser mice falter and fail, these mice move like champs across the clean, transparent glassy surface tracking the movements accurately on your computer screen. This is because hidden under the curvy exterior is a wonderful technology with a deep, dark history.
Around the turn of the 19th century, the field of optics especially the realm of microscopy saw a huge uptick in innovation thanks to the pioneering work of Charles Spencer and others who followed in his wake. It was around this time that a German Zoologist working long nights in his lab used a radically new technique for lighting up his microscopic samples for study. But what he saw underneath the lens, churned his stomach in awe and fear. Under the new lighting technique, his familiar samples looked… alien… alive. The technique was so powerful that his findings went on to give birth to a new and highly controversial field of study ‘Live Blood Analysis’, and for the first time shook the foundations of the theory that blood was not sterile, as was widely believed at that time, by showing minuscle packets of moving life that were later termed ‘bions’. The German zoologist concluded from his observations that these bions can change from being harmless in normal blood to becoming harmful and infectious in highly acidic blood conditions. They were thus responsible for sowing the seeds for illness and ageing in the long term and this knowledge enabled him to predict the ‘Medical Future‘ of those, whose blood he could analyse.
With the technique opening his eyes to a side of the world previously unknown to man, a steady stream of discoveries came out of his lab challenging many assumptions of medical study that, until then, had been taken for granted. “If Bions are life then, as humans, are we permitted to look into it and study it?” questioned the God-fearing society. Some even went so far as to calling it Sorcery(see footnote 1), and the fear and uncertainty against the technology steadily rose in the hearts of the common man. Conventional Scientists were not far behind. Scoffing at his claims that Bions can Pleomorph(change their form and their function from useful to harmful depending on their surrounding environment), they called him a fraud and strove to bring down his work and any who chose to follow it. His findings were too progressive, too different, for the world to accept at that time. And they did the obvious thing… dismissed his work as ‘Forbidden Science’, and threw the technique which helped him know it all, into a dark corner of the scientific world hoping it will be forgotten from human memory forever.
But the technique that gave Günther Enderlein a page in the history books as the founder of ‘Live Blood Analysis’ and as the first proponent of plemorphism, could not be destroyed so easily. Dark-Field illumination, the science that was known to man for centuries and brought into limelight by Enderlein, quietly went underground and out of public sight, where it would spend decades gathering dust until a Swiss manufacturer unaware of Dark-Field’s maligned medical history, would come to think up a simple and clever use for it in their flagship electronic product – the computer mouse.
In 2006, Logitech released what would then go on to become their most succesful product ever – the Revolution MX computer mouse. But things were still not perfect yet. The mouse had a lot of useful innovations but over 40% of the customers, Logitech surveyed, had the same problem – they needed the mouse to work on transparent glass surfaces and mouse-pads were just too cumbersome to carry around for these ‘on-the-go’ users.
Computer mice work by reading surface details from the light scattered by the surface, then comparing the image with the reference image taken microseconds earlier to gauge how far and in which direction the mouse has moved in that time interval. On glass, the laser from the mouse just passes through and without light reflecting back to the mouse’s sensor, there’s no way to use Laser-tracking mice on glass. Unless… the mouse is somehow able to receive the miniscule amounts of light bouncing off of the microscopic indentations and imperfections inside the glass itself. Putting a lab microscope inside the the mouse was out of the question. It was then that Dark-Field illumination found its way onto Logitech’s drawing board.
Dark-Field Illumination:
Before going into how Dark-Field illumination works, here is a comparison of the same microscopic sample under standard illumination on the left and Dark-Field illumination on the right.
This is the secret to Dark-Field’s charm – the high contrast imagery possible using the technique. As the size of the samples decreases, the effectiveness of Dark-Field, when compared to normal lighting, goes up even higher. What makes Dark-Field even more useful is that the principle behind the technique is so simple and clever that even laymen can put together a Dark-Field setup in their house. This, along with the superb high-contrast imagery, combine together to give Dark-Field the potential to be a disruptive technology when applied in the right areas.
Here’s how it works. In the standard lighting setup, light is shone on the subject and the scattered light is captured and recorded. The problem? Except for the minuscule quantity of light that gets scattered away, all the light that falls on the object makes its way into the final picture thereby washing out the little details(giving us the white-ish sample on the left in the picture above).
In Dark-Field, the light(bottom-section of pic 1) is split into two-beams(using a simple metal splitter like the one in pic 3) that are then made to cross each other and cancel themselves out just as it reaches the sample(mid-section of pic 1). The light that reaches the viewer’s eyes(top-section of pic 1) now consists only of the light that is scattered off of the sample. This is why, though Dark-Field uses a similar setup as standard illumination, it offers significantly higher contrast pictures(like the sample on the right in the picture earlier). Simply put, picture taken with the standard lighting setup accepts all light except the light scattered by the sample while a picture taken using Dark-Field does the opposite – rejects all light except the light scattered by the sample. Thus Dark-Field creates a contrast between the subject and the background so that the background is dark and the subject is light. Dark-Field’s charm lies in this simplicity with which it achieves amazing results.
In Dark-Field, Logitech finally found the solution to the problem of using computer mice on glass, a full 40 years after Bill English used the word ‘mouse’ in his 1965 publication “Computer-Aided Display Control”. On regular surfaces with plenty of texture, such as a formica and wood tables, Dark-Field mice behave the standard way which is to use a single laser to take pictures of the texture and use it for tracking the pointer on the screen.
However, on extremely smooth surfaces like glass, Dark-Field mice automatically turn on their second laser and switch to advanced (microscopy) tracking mode. Now the surface appears black, while dust and other residual details inside the glass show up white. For a Dark-Field mouse a glass table actually looks like a starry night. For customers, this means that they can use their mouse just about anywhere.
Mouse-pads everywhere… R.I.P.
Logitech has just started with the Dark-Field revolution and the technology is expected to make its way even deeper into their product line-up in the near future, especially with their gamer mice. And mouse-pad less computer mice is just one of the many possible applications of Dark-Field. Imagine super-high-precision machining where the surface being machined is continuously scrutinized under Dark-Field for cracks or abnormalities. Imagine silicon chip manufactures using Dark-Field to make sure chip interconnects and features match the schematic right down to the letter. The possibilities are limited only by human creativity.
40 years after getting kicked out of conventional Medical Science, Dark-Field has finally found a new home in Electronics. This time, there appears to be a chance for a happy ending.
Footnotes:
- This continues even today.
- This post does not endorse the Logitech products cited here, as there is so much more to a mouse than just tracking technology like Ergonomics, Battery Life, Trouble-Free function, and other factors.The purpose of this post is to highlight how an oft-maligned and misunderstood technology can find new uses in an entirely new field, in this case, Dark-Field transforming from being infamous in the medical field into a potentially disruptive technology when crossing over into the electronics field.
You can read customer reviews for the Logitech Anywhere MX wireless mouse here
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For the Logitech Performance MX wireless mouse, customer reviews can be found here.
- Logitech’s current line-up of Dark-Field mice do not work on Laboratory grade glass or glass thinner than 4mm, unless there is some dust on the surface. This should change as more advanced Dark-Field optics becomes cheap enough for use in mass manufactured devices.
- For those curious about the history after the Dark-Field issues, Crick and Watson’s work on the DNA laid the foundation for modern medicine and eventually lead to the debunking of Enderlein’s theory that ‘Bions’ were alive. They were later termed ‘Prions’ as they were found to be unique protein based structures mimicking certain aspects of living creatures with the exception of reproduction. Prions are responsible for Mad-Cow disease among others giving credence to Enderlein’s observations from 40 years ago, and as medical science learns and understands more, we will see Enderlein’s work being revisited quite often.
- Dark-Field Microscopy for Live Blood Analysis is still not FDA-approved as the structures reveled by Dark-Field and their exact function are not fully understood even today. Hence, the use of Dark-Field microscopy as the basis for diagnosis must be avoided as prescribing medication based on partial knowledge can be dangerous. Live Blood Analysis using Dark-Field microscopy is said to be able to predict the onset of several illnesses/medical conditions as one can view very tiny objects within blood, such as vitamin and mineral deficiencies, hormonal imbalances, fungal infections, parasite infestations, digestive problems, heavy metal toxicity, predisposition to cancer etc, and can be used as a casual inquiry into one’s own medical future. Although, it must be reiterated that the results of this casual inquiry must not be taken seriously on their own and any suspicion must be backed up by conventional medical tests by a registered medical practitioner.
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