| Transducer | Operates by: | Is it steered? How? | Is it focused? How? | Image shape | Electronic or Mechanical? |
| Linear sequenced array | sequencing | no | no – fixed focus | rectangle | Electronic |
| Curved sequenced array | sequencing | yes – transducer shape/element arrangement | no – fixed focus | “blunted” sector | Electronic |
| Phased linear array | sequencing | no | yes – phasing | rectangle | Electronic |
| Phased curved array | sequencing | yes – transducer shape/element arrangement | yes – phasing | “blunted” sector | Electronic |
| Vector | sequencing | yes – phasing | yes – phasing | “flat top” sector | Electronic |
| Linear phased array | phasing | yes – phasing | yes – phasing | “pointed” sector | Electronic |
| Annular array | phasing | yes – mechanically | yes – phasing | “notch” sector | Electronic (with a mechanical reflector for steering) |
| Oscillating Element | mechanical means | yes – element movement | no – fixed focus | notch sector | Mechanical |
| Rotating group of elements | mechanical means | yes – element movement | no – fixed focus | notch sector | Mechanical |
| Oscillating reflector | mechanical means | yes – reflector movement | no – fixed focus | notch sector | Mechanical |
| Linearly translating element | mechanical means | no | no – fixed focus | rectangle | Mechanical |
