The invention relates to liquid crystal lenses having dynamically switchable light transmission, including: a shutter (2) including two transparent substrates (21, 22) and a nematic liquid crystal layer (20) arranged between the substrates (21, 22); and a control circuit capable of alternately applying a bias voltage or a relaxation voltage across the liquid crystal to render the shutter (2)clear or opaque, the falling edges between the bias voltage and the relaxation voltage having a duration of 80 to 900 μs.