Background
PBM Medical Technologies Ltd developed SightGuard, the company's first phototherapy device, intended for the treatment of dry AMD (dry age-related macular degeneration). The device is a mask the patient wears over the eyes, and the treatment is delivered by light.
The challenge
In light therapy, the light itself is the treatment. The LEDs must deliver a precise wavelength range and a precise intensity, and this has to repeat in every session and hold throughout each session. On top of that come the demands of a home product: the device runs on rechargeable batteries, so the battery voltage drops during use, and the patient has to operate it alone, with no staff member present.
What we built
- Precise LED drive: a drive circuit that holds the intensity at the required accuracy, even as the battery voltage changes.
- Rechargeable battery power: power management and a charging circuit, so the device is charged at home and ready for the next session.
- Firmware: management of the treatment, the LEDs and the battery state.
- Home use: simple one-button operation, suited to a patient using the device alone.
The result
A home treatment device that runs on a battery and delivers light at the intensity and wavelength range the treatment requires. Because accuracy depends on both the drive circuit and the code that runs it, one engineer designed both, and there was no need to sort out between teams where a problem came from. The client had a single point of contact: they talked directly to the engineer, with no project manager in between. A large company is a better fit when you need a full team working on several products in parallel, but for focused development like this, working directly is faster and costs less.
