three-gun
three-halves-power
three-high
three-hinged
three-indication
three-input
three-jawed
three-lane
three-layer
three-lens
  three-level
three-neck
three-pass
three-phase
three-plate
three-play
three-point
three-pointer
three-product
three-quarter
three-quarter-wave

    three-level laser

     лазер с трехуровневой схемой, лазер с трехуровневой энергетической схемой

     трехуровневый лазер