Every laryngoscope does the same job: it lights the airway so a clinician can see the vocal cords and place a tube. The two main systems differ in where the light is made and how it reaches the tip of the blade. That single design choice shapes reprocessing, service life and compatibility across a hospital.
How a conventional laryngoscope works
In a conventional, or hook-on, laryngoscope the lamp sits on the blade itself. When the blade is opened onto the handle, contacts on the hinge close the circuit and the batteries in the handle light the lamp.
- Simple, familiar and cost-effective.
- The lamp and contacts are part of the blade, so they go through every cleaning and sterilisation cycle.
- Lamps need replacing over time, and corroded contacts are a common cause of flickering light.
How a fiber-optic green-system laryngoscope works
In a fiber-optic laryngoscope the light source is in the handle. A bundle of optical fibers, or an acrylic light guide in single-use blades, carries the light from the handle to the tip of the blade. The fitting is defined in ISO 7376 and identified by a green marking, which is why it is called the green system.
- No bulbs or electrical contacts on the blade, so there is nothing electrical to damage during reprocessing.
- Light is cool and evenly spread at the tip, with xenon or LED sources in the handle.
- Green-system blades and handles from different manufacturers built to ISO 7376 can work together.
Do not mix the two systems
A conventional blade will not light on a fiber-optic handle, and a fiber-optic blade will not light on a conventional handle. The hook-on hinge can look similar, so standardising on one system per department, and labelling stock clearly, avoids a dark blade at the worst possible moment.
Which one should you choose?
Many hospitals in Europe and North America have standardised on the fiber-optic green system because of its durability and reprocessing benefits. Conventional systems remain a sound, economical choice where they are already in use and where budgets matter most. We make both, so we can supply whichever system your department runs, or help you plan a move from one to the other.