Fingertip Microscope iMicro Q3 (late-2023 Kickstarter project from Shanghai)

Phone-camera-microscope’s-eye view of the surface of the wrist wrest pad glued onto a computer keyboard.

A 2023 Kickstarter project for a high-magnification mobile-phone-camera microscope that closed to new backers last December (iMicro Q3 – A Fingertip Microscope toward the Optical Limit [Kickstarter] / iMicro Q3 – A fingertip microscope with super 700nm resolution [YouTube]) began shipping its rewards recently and a slim bubblepack-lined manila envelope containing several iMicro Q3s landed at my doorstep a couple of days ago now. The shakycam video clip above was recorded with one of these pinky-nail-sized lenses stuck onto the lens of the camera on the Android phone I use to snap some of the photos I post here. When the camera swoops over a dark, craggy surface, you’re seeing it slide across the smooth-to-the-naked-eye wrist rest pad on a computer keyboard.

A differently-lit photo of a different randomly-selected patch of wrist rest than the one in the video clip.

The image above is a still image taken under slightly different light and, IIRC, a very little bit of pinch-zoom (aka digital zoom) in the phone’s camera app. The small colorful inclusions, the tiny red bits and yellow bits, may be debris, perhaps bits of yellow and red plastic from when I’ve shortened plastic zip ties, that has been ground into the surface over time. Or the padding may have been manufactured from recycled plastic and those are crumbs that were resistant to whatever colorant was used or perhaps tiny microplastic contamination introduced inadvertently during manufacturing. I could cut into the material with a clean blade and check newly-exposed strata of the padding, but the pull of curiosity in this instance isn’t strong enough to move me to the point of marring a perfectly respectable-looking and properly-functioning keyboard.

A word about lighting and the iMicro Q3: it has no built-in LEDs and the lens has to be nearly pressed against the surface being investigated. If you’re looking at something opaque or even something partially transparent under normal light, you may wind up using something like a keychain flashlight unless your smartphone has bright LEDs embedded very near its built-in camera. I used the first battery-powered LED light that I found within reach to light up the relevant region of keyboard padding, from the side, as best I could. For the photos and videos taken of a microscope calibration slide (embedded further along in this post), ambient light was sufficient.

Below is a photo of the calibration slide, snapped using the phone’s un-augmented camera, but with a bit of digital zoom. I can’t recall how much pinch-zoom I used because I didn’t think to take a screenshot before or after taking the photo.

Microscope calibration slide with a 0.01mm-per-division scale bar inside a circle.

Next up is an image that shows the new Kickstarter-project stick-on microscope on the left (which has a claimed magnification of 1200x) and the much larger and lower-magnification (note the 200x printed on the casing) clip-on smartphone-camera microscope with a squarish plastic case on the right. The whitish-gray annulus around the 200x microscope is a small but effective LED ringlight. The big microscope (which I’ll henceforth refer to as 200x or Good ol’ 200x) is the one I’ve used frequently here in the past and it sells for somewhere in the neighborhood of CN¥ 138 (roughly US$19) on Taobao but you can find it under various brand names and in different colorways for a little more or a little less from different sellers in different parts of China. The same device is going for US$ 36.98 (marked down from $42.99) on Amazon.com at the moment with either a black or a white plastic casing.

On the right, a clip-on phonecam microscope which I've been using for a while. On the left, a stick-on phonecam microscope that provides a significantly higher magnification. — On the right, a clip-on phonecam microscope which I’ve been using for a while. On the left, a stick-on phonecam microscope that provides a significantly higher magnification.

Smartphone microscopes are available in different form factors and I’ve used a variety of different types over the years and 200x has been the all-time champion design, at least until now. It’s a squarish puck with beveled corners that’s about a centimeter thick and approximately 3cm long and wide that slides in a separate plastic clip from which it could be easily extracted, though I’ve never needed to separate the microscope from the clip.

Most of the other smartphone microscopes I’ve used have been long and vaguely barrel-shaped and have had useful features, like focus adjustment knob. Good ol’ 200x has no means of adjusting focus, but it has been very good in one respect where the rest have been terrible: staying in position. A plastic thingamajig that clips onto a smartphone behaves like a cantilever beam. All else being equal (i.e. unrealistically assuming the smartphone microscope is a solid rod of material of uniform density), the longer it is and hence the further it protrudes from the phone, the greater the shear force and bending moment, which reach their maxima at the base (where the clip holds the microscope on the phone). The shear force translates into a tendency for the microscope to slide down or (if the phone is held at an angle) from side to side or upwards, with the result that its lens and the phone camera’s lens fall out of alignment (and you get a black screen or an unmagnified view if the thing slides far enough). The bending moment results in a tendency for the grip of the microscope’s clamping or jaw mechanism to lose its grip and for the body of the microscope to tilt forward so that its base is no longer flat against the case of the phone, but pointed upwards at the back of the microscope and maybe looking partly at the inner surface of the tubular hole inside the microscope.

A thinner design (like a squat, flat, centimeter-thick puck) means less cantilevering and so less shear force and a smaller bending moment, making the thingamabob (a clip-on smartphone microscope in this case) less wiggly and fiddly to use. Good ol’ 200x’s clip doesn’t even have any adhesive-backed pads of grippy rubbery material stuck to its phone-contacting regions.

The allure of the iMicro Q3 (which I’ll refer to as Q3 from here on out) is a much higher magnification (1200x vs. 200x, so sixfold) and the luxury of not having to bother with clips and clamps (which partially cover the screen) because the thing is supposed to stick to the phone exterior. Having used the Q3 a bit now, I can attest to the stickiness being real and working. You grasp the thing firmly and pop it off whatever its on and press it onto something else smooth and flat and it stays until you pluck it off again.

I’ve never verified the magification on Good ol’ 200x, but the Q3 does give a six-times-higher magnification than the 200x. The screencaps below, merged into one image but unedited aside from the placement of little square overlays containing an image of 200x and the Q3 above their respective screenshots, show the view through 200x (top) and through the iMicro Q3 (bottom) in the phone’s default camera app with no additional zoom (i.e. no digital/pinch zoom).

Paired screenshots of the built-in Android camera app looking through the 200x microscope (top image) and through the iMicro Q3 microscope (bottom) at a microscope calibration slide.

Here’s another pair of screencaps, this time looking at the same wrist rest pad material featured in the short video clip and still photo taken with the Q3 at the top of this post:

This time, looking at an opaque bit of rubbery material instead of at a glass microscope slide, my attempt to light the target with a LED light notwithstanding, the camera app went into Night Sight mode while I was using the Q3. Regarding the pairs of partially transparent blue-green overlay strips running from side to side in the screenshots, they’re from the EdgeBlock Android app, which I hadn’t been running when I took the calibration slide screenshots. The wrap-aroundness of the screen on the phone being used here makes it difficult to hold securely without the touchscreen registering a contact somewhere on either edge of the screen and consequently blocking/ignoring other touch gestures (e.g. pressing the round take-a-photo button).

The greater the magnification, the greater the jitter from infinitesimal hand shakiness, so my apologies for the blurriness of the target in these camera-app-screen-view-through-Q3 screencaps. Taking a screenshot on Android, without installing a third-party easier-screencaps app or remapping buttons or taking other extra steps is unacceptably fiddly anyway. Simultaneously pressing the POWER and the VOLUME-DOWN half of the VOLUME unibutton without wiggling the phone enough to jumble the view through a high-magnification lens isn’t as easily accomplished as one might expect.

Here’s a Q3, no-extra-zoom photo that’s less blurry than the screencap but not as good as the visuals topping this post, with the Q3 seated a wee bit off-center relative to the phone’s camera lens:

Slightly better wrist rest pad photo taken through the Q3.

So my verdict is that the iMicro Q3 delivers on its promises and is quite usable and useful. But my good ol’ 200x isn’t going anywhere. Two-hundred-times magnification (or whatever it actually is) is often more than sufficient and very useful. The herky-jerky video of me scrolling the 1 DIV = 0.01mm that I clipped and made into a thumbnail for this post was taken with the 200x, for example, as were the photos below, all views of a gently-used ATTEN T130-2.0SK soldering iron tip: