Laboratory Safety and Table Covers

Our client was converting a room into a quantum optics laboratory—the lab was to include a large optical bench on which lasers would be mounted. The client’s requirements were to ensure the safety of both the room and the optical bench and to design a system capable of handling Class 4 lasers. The system was to support operation in various safety modes.

Among the requirements was also the ability to control the system remotely via the local network, so that the laboratory could be visually monitored and safety features controlled from a single device. Integration into the laboratory’s existing electrical wiring and cabling was also important.

For a newly built quantum optics laboratory, we designed and installed a technical security system in accordance with the client’s specifications, which meets the requirements for working with Class 4 lasers. The solution includes access control to the room, monitoring of the optical bench’s safety enclosure, and management of interlock circuits across multiple operating modes.

The system is based on a programmable safety unit located in the central control cabinet. It collects data from sensors and controls the laser power supply. The main optical table is equipped with an aluminum enclosure (2000x1000x300 mm) with black Alubond panels. The enclosure is divided into three sections with removable covers, each of which is monitored by interlock switches. Inside the enclosure is a secondary control panel for the direct connection of up to three laser circuits.

The system operates in three modes, which are switched using a key-operated panel inside the laboratory:

• Red Mode: The door lock is engaged, and the system allows Class IV lasers to operate. The table interlock is bypassed in this mode. If the door interlock is bypassed (by forcing the magnetic lock), the interlock circuits are immediately disconnected and the lasers are shut down.
• Yellow Mode: The door lock is unlocked, and the laser may only be operated with the cover closed. When this measure is observed, the system meets the requirements for Class I equivalent operation. Opening the cover interrupts laser operation. Entering the room through the door does not interrupt laser operation.
• Green mode: The lasers are turned off, the locks are deactivated, and the table covers can be opened at will.

A warning beacon, a Laser Kill button, and a touchscreen display with a mini PC are located at the entrance to the laboratory. The display shows the current operating mode and the status of the safety loops. The entire installation is connected to the local network, which allows for remote visual monitoring and management of the components. The cabling is routed through separate cable trays along the perimeter of the room.

The control unit’s capacity was designed with room for future expansion to include an additional optical table, a second safety enclosure, and two additional interlock circuits.

The project also received media attention. The Novinky.cz website reported on the opening of the newly operational CTU quantum laboratory in a popular science article. This CZK 30 million laboratory will serve not only for science and research but also to train students on the technologies of future critical digital infrastructure.

And it is precisely the security of this laboratory that we provided in this project. Already in the opening photo of the article, you can see the optical bench with our enclosure already covering the optical setup.