|
|
| |
| Förkortningen betyder |
| USD = Ultra Sonic Drive |
| |
|
|
| |
| Förklaring från Tamron |
Tamron’s USD works with the high-frequency ultrasonic vibrations that are produced by a ring called a ‘stator’. Energy from the vibrations is used to rotate an attached metallic ring known as the ‘rotor’. Piezoelectric ceramic, an element that produces ultrasonic vibrations when voltage of a specific frequency is applied is arranged in a ring formation on the stator. This electrode configuration of piezoelectric ceramic causes two ultrasonic vibrations to occur in the stator.
By effectively combining these two ultrasonic vibrations, it is possible to convert the energy from the vibrations that produced simple motion into energy known as ‘deflective traveling waves’, which then moves around the circumference (rotation direction) of the ring.
With the USD, the friction between these deflective traveling waves created on the metallic surface of the stator and the surface of the rotor produce force, causing the rotor to rotate. The focusing ring lens, which is linked to the rotor, is thus moved, creating a fast and smooth auto-focus drive. |
| |
| Se länkar |
|
|
|
|
|
| Följ oss på Facebook |
| Via vår Facebook-grupp får du nyheter om allt som rör objektiv i allmänhet och Objektivguiden i synnerhet. |
|
|
|
|
|
|
| Se objektiv för just din kamera |
| Nedan visas några modeller (se alla) |
| Canon EOS 500D |
| Canon EOS 80D |
| Nikon D5300 |
| Canon EOS 1D |
|
