The first step we took was removing the top of the housing so we could look inside the device. Once we had a clear view of the interior, we planned our disassembly approach. We decided to work from the back to the front, starting with the PCBs. We removed them one at a time, though some were difficult to detach due to wires that were soldered or welded to various components, including the top of the housing.
bird’s eye view of device with lid off
welded wire to top of housing lid
We continued working through each PCBA, treating them as subassemblies. The first one we removed was fairly straightforward, but as we progressed, we encountered others that required wire cutters. Many of these PCBs were simply floating inside the device, not secured to anything except for their wired connections, which were either soldered or adhered to electrical components.
First PCBA removed
PCBA removed with wire cutters
Once we removed the free-floating PCBAs, we focused on those that were structurally secured. There were three PCBs that were firmly attached, requiring more careful disassembly with screws. After extracting those, we moved on to the internal housing of the optical subsystem, which consisted of plastic parts that helped secure it inside the device. This step proved challenging, as this subsystem was connected to the most components in the device.
optical subsystem
plastic structure components that secured optical system
The last two PCBs were particularly intricate, as they were linked to multiple parts. When we reached the optical system, disassembly required extensive unscrewing. We also encountered a mini PCBA attached to the optical subsystem, which we believe was the sensor. From there, we dismantled the optical components, including lenses, optomechanical parts, and a circulator.
lens
web of optical fibers we were trying to take apart from optical circulator
More PCBA removal
Once we had removed all the internal components, we returned to the overall housing. We took off the handle and side panels, which helped contain everything. At this stage, we also explored how much further we could disassemble the optical subsystem before wrapping up the process.
me trying to figure out how the heck this was made
side handle disassembly
outer housing disassembly
Our team disassembled an Optical Coherence Tomography (OCT) machine, revealing insights into its assembly, components, and design choices. The machine was primarily secured with traditional fasteners, such as Philips and Torx screws, while some smaller subassemblies utilized snap joints. We observed a mix of off-the-shelf components—such as PCB parts, screws, optical lenses, heat sinks, and optical fibers—alongside uniquely machined elements, including a shocking custom L-bracket that was machined by we think the med device tinkers.
The disassembly process showed that certain sections of the device were designed for accessibility, while others were not intended to be taken apart. The front panel, secured with Torx screws, housed components that appeared easier to access for maintenance. In contrast, the back portion contained tightly integrated parts, some secured with adhesives to prevent disconnections. The light source, a crucial component of the optical system, seemed intentionally difficult to access, reinforcing the idea that some sections were designed for durability rather than repair.
Despite its complexity, the OCT machine seems to be recyclable, as no hazardous materials were evident during disassembly. The internal components were disorganized, with several free-floating PCBAs. We progressed slowly from the back to the front of the device, cutting through various PCBs and structural components to expose the subsystems. The PCBAs were arranged in subassemblies, suggesting a structured yet manual assembly process. We think the tinkers were the ones who put the whole thing together by hand.
One of the most striking observations was the level of human involvement in manufacturing. Hand-soldered PCBAs, adhesive applications on fasteners, manually tightened screws, and neatly secured wire connections all indicated that this device was likely assembled by hand. This highlighted how even advanced medical imaging technology could be produced in a controlled but hands-on manufacturing environment.
Another interesting discovery was the optical subsystem, particularly the optical fibers routed around a fiberglass board connected to a sensor. The optical components required precise alignment, and I was surprised by the tiny size of the lenses—some smaller than a dime. The device relies on an effective optical system yet the optical components only made up 6% of the total weight of the device. Its interesting how the optical components play such an important but are extremely lightweight relative to the other subsystems.
I am super grateful to have this opportunity to take apart this OCT….until the next project 😛
Link to worksheets:
Equipment Take Apart Lab Worksheet.pdf
Clean up:
