Sonic device
A sonic device in an embodiment includes a sonic transducer unit and a sonic propagation unit. The sonic transducer unit performs at least one of transmitting and receiving a sonic wave, and has a sonic function surface to configure at least one of a wave transmitting surface and a wave receiving surface. The sonic propagation unit includes: a substrate having a pair of electrodes; an electroadhesive element expressing body including a resin crosslinked body arranged on the substrate, and particles dispersed in the resin crosslinked body; and a power supply to apply voltage to the pair of electrodes. The sonic propagation unit is provided on the sonic function surface of the sonic transducer unit, and the electroadhesive element expressing body in the sonic propagation unit comes into contact with a test object.
1. A sonic device comprising:
a sonic transducer unit configured to perform at least one of transmitting and receiving a sonic wave, and having a sonic function surface to configure at least one of a wave transmitting surface and a wave receiving surface of the sonic wave; and
a sonic propagation unit comprising: a substrate having a pair of electrodes; an electroadhesive element expressing body, configured to come into contact with a test object, comprising a resin crosslinked body arranged on the substrate, and particles dispersed in the resin crosslinked body; and a power supply configured to apply voltage to the pair of electrodes, the sonic propagation unit being provided on the sonic function surface of the sonic transducer unit.
2. The device according to claim 1 , wherein the particles are electric rheology particles.
3. The device according to claim 1 , wherein the electroadhesive element expressing body further comprises a charge transport material contained in the resin crosslinked body.
4. The device according to claim 1 , wherein the electroadhesive element expressing body further comprises conductive particles contained in the resin crosslinked body.
5. The device according to claim 1 , wherein the electroadhesive element expressing body further comprises a process oil contained in the resin crosslinked body.
6. The device according to claim 1 , wherein a ratio of acoustic impedances of the particles and the resin crosslinked body is in a range of 0.001 or more and 1000 or less.
7. The device according to claim 1 , wherein the particles have an average particle size of 100 μm or less.
8. The device according to claim 1 , wherein the electroadhesive element expressing body has a porous structure.
9. The device according to claim 3 , wherein the electrodes contain a metal having a work function having a difference from a highest occupied molecular orbital of the charge transport material falling within 0.5 eV.
10. The device according to claim 4 , wherein the electrodes contain a metal having a work function having a difference from a work function of the conductive particles falling within 0.5 eV.
11. The device according to claim 1 , wherein the electroadhesive element expressing body has a function of accommodating the particles in the resin crosslinked body when the voltage is applied to the pair of electrodes from the power supply, and causing a part of the particles to project from a surface of the resin crosslinked body when the voltage is eliminated.
12. The device according to claim 1 , wherein the sonic device is an ultrasonic transducer or a sonic receiver.
13. The device according to claim 1 , wherein the sonic propagation unit further comprises a polymer-containing layer having a Young's modulus of 1 GPa or less, and disposed between the sonic function surface of the sonic transducer unit and the substrate.
14. The device according to claim 13 , wherein the polymer-containing layer is fixed to the sonic function surface of the sonic transducer unit and a surface on opposite side of a surface of the substrate on which the electrodes are provided, each through an adhesive layer.
15. The device according to claim 13 , wherein the polymer-containing layer contains a slide-ring elastomer.
16. The device according to claim 13 , wherein the polymer-containing layer has a shape with a peripheral region and a central region having a thickness thicker than a thickness of the peripheral region.
17. The device according to claim 1 , wherein the sonic propagation unit further comprises a layer containing a slide-ring elastomer and disposed between the sonic function surface of the sonic transducer unit and the substrate.