Smoke particles are an aerosol (or mist) of solid particles and liquid droplets that are close to the ideal range of sizes for Mie scattering of visible light. Depending on particle size, smoke can be visible or invisible to the naked eye. This is best illustrated when toasting bread in a toaster. As the bread heats up, the products of combustion increase in size. The particles produced initially are invisible but become visible if the toast is burned.
The visibility problems in smoke is very much alike those in fog or haze, albeit being more dense in many cases. LYYN real-time visibility enhancement performs best in disperse types of smoke, e.g. smog or smoke-filled rooms.
Please see more examples on the fog page.