Have you ever felt the urge to touch a lens like a button or a joystick? I built some soft silicone blobs that can transform camera lenses into physical input elements.
I tried to squeeze a paper into the shape of a YouTube video: https://youtu.be/lyz52IzMcnM
Quick summary:
If you want to enable some kind of on-lens interaction you need to track fingers on or slightly above a camera lens.
With a piece of soft and clear silicone, it's easy to create a protective barrier for the lens, but the finger will be out of focus and just a skin-colored smudge.
By molding the clear silicone in the shape of a positive lens, it's possible to refract the light in a way that the focus of the camera will always be on the fingertip if it touches the silicone.
If there is a pattern printed on the silicone, it's straightforward to detect the deformation of the pattern and detect what the fingers do with the silicone.
You can find the pre-print paper on arxiv: https://arxiv.org/abs/2307.00152
and additional info here: https://volzo.de/thing/lensleech/
Cameras provide a vast amount of information at high rates and are part of many specialized or general-purpose devices. This versatility makes them suitable for many interaction scenarios, yet they are constrained by geometry and require objects to keep a minimum distance for focusing. We present the LensLeech, a soft silicone cylinder that can be placed directly on or above lenses. The clear body itself acts as a lens to focus a marker pattern from its surface into the camera it sits on. This allows us to detect rotation, translation, and deformation-based gestures such as pressing or squeezing the soft silicone. We discuss design requirements, describe fabrication processes, and report on the limitations of such on-lens widgets. To demonstrate the versatility of LensLeeches, we built prototypes to show application examples for wearable cameras, smartphones, and interchangeable-lens cameras, extending existing devices by providing both optical input and output for new functionality.
This was -- in its entirety -- quite a huge chunk of things to test, try, and learn. Especially starting from zero.
If you want to know more about how silicone molding with integrated lenses can be done, I did a separate video about this topic:
If you want to learn how the application examples work, I did a video about the hybrid viewfinder (and viewfinders in general):
Christopher Getschmann