Electronic circuit and control system for the on-screen device “dejavu”

We designed the electronic circuit for “dejavu,” a compact prop featured in the film Mystery Arena, and developed a dedicated control application for use on set.

PROJECT

Film “Mystery Arena”

For Mystery Arena, released on May 22, 2026, we designed the circuit and control application for the on-screen device “dejavu.” The required functions were integrated into a constrained enclosure, while multiple units could be controlled reliably during filming.

CHALLENGE

A battery, LEDs, wireless communication, and a charging connector had to fit within a space of approximately 4.5 cm × 1–2 cm. The system also needed to provide expressive lighting, stable operation, and quick control and monitoring of multiple devices on set.

OUR ROLE

What invilab delivered

Designed the compact electronic circuit and PCB
Implemented low-power control to extend battery life
Developed an app for brightness, color, RGB, and five flashing patterns
Added monitoring for signal strength, battery level, and internal temperature
Implemented automatic power saving after disconnection and iterated during filming

OUTCOME

The crew could adjust the lighting of multiple devices and monitor their status on set. Both the devices and application were updated throughout production in response to practical filming requirements.

Project gallery

Compact electronic circuit installed inside dejavu — Electronic circuit and PCB fitted inside the compact enclosure

Dedicated application controlling dejavu lighting and status — Dedicated application combining lighting control and device monitoring

Images provided by invilab inc. (PR TIMES press materials)

Project team

INAC Co., Ltd.: Exterior design and production for “dejavu”
invilab inc.: Electronic circuit, PCB, embedded control, and dedicated application development

View the PR TIMES announcement (Japanese) ↗Official Mystery Arena website (Japanese) ↗