We’ve been developing a compact thermal overlay system designed to integrate with common night-vision platforms like the PVS-14, RNVG, BNVD, and other dovetail housings. The goal was simple: provide the functional advantages of a thermal overlay in a lightweight, practical package without the price barrier of systems like ECOTI.

The result is the HELIOS-T (Helios Thermal Overlay System).

Before getting into the details, one thing needs to be clear because it will likely come up:

This is not a BCOTI clone or rip-off.

BCOTI is a great open-source project and deserves credit for helping prove what is possible with accessible components. However, the HELIOS-T is a ground-up hardware and firmware design intended to be a complete, field-ready product, not a DIY electronics project.

Yes — the HELIOS-T uses the same thermal camera module and Micro-OLED display used in BCOTI builds. Those components are commercially available and widely used in the thermal hobbyist community.

Everything else is our own design, including:

• Custom integrated PCB architecture
• Non-open-source firmware developed specifically for this system
• Simplified single-button user interface
• Quick-release mounting interface for rapid install/removal
• One-time image alignment process (no constant fiddling with overlays)
• Integrated connectors and internal layout designed for durability

BCOTI is awesome if you want to build something yourself. But realistically, building one requires:

• Micro-soldering skills
• Embedded electronics knowledge
• Firmware configuration
• Access to tools and test equipment
• 3D printing capability
• A fair amount of time troubleshooting and tuning

For many people that’s part of the fun.

For others, it’s not practical.

HELIOS-T exists for users who want a ready-to-run thermal overlay system without having to build and debug it themselves.

Key highlights:

• 256 thermal core for reliable heat detection
• 1280×800 Micro-OLED overlay display
• Approx. 85g total system weight
• 30% smaller than early prototypes
• USB-C powered
• White Hot / Black Hot / Outline / Fusion modes
• Single 5-position control button
• Quick-detach mounting system
• Simple one-time IIT alignment

The unit injects thermal data directly into the night-vision optical path, giving users improved detection capability in low-light, obscured, or complex environments.

The focus of the design has been:

• Reliability
• Simplicity of use
• Compact size
• Practical field operation

This project is still evolving and we’ll share more development details as things progress.

If you enjoy building electronics and experimenting with firmware, BCOTI remains an awesome project and we absolutely encourage that community.

If you want a fully integrated system designed to just work, that’s where HELIOS-T comes in.