1 / 15

Ultrasound Principle 超音波原理

Ultrasound Principle 超音波原理. Diagnosis Imaging System 影像診斷系統. Sound wave. Wavelength. l. 波長. Pressure. maximum. 振幅. Amplitude. Pressure. minimum. 1 Cycle. 1 Cycle. 1 Cycle. 週期. 週期. 週期. Sound wave. dB. Amplitude Frequency Velocity. MHz 1,000,000 次 / 秒. 1540 m/s in body.

karina-baldwin
Download Presentation

Ultrasound Principle 超音波原理

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Ultrasound Principle超音波原理 Diagnosis Imaging System 影像診斷系統

  2. Sound wave Wavelength l 波長 Pressure maximum 振幅 Amplitude Pressure minimum 1 Cycle 1 Cycle 1 Cycle 週期 週期 週期

  3. Sound wave dB • Amplitude • Frequency • Velocity MHz 1,000,000 次/秒 1540 m/s in body

  4. 折射與反射 Refracted Refracted Reflected Reflected wave wave wave wave Propagated wave Medium #1 Medium #2

  5. Power and Intensity dB Intensity Ratio Amplitude Ratio 70 10,000,000 10,000 60 1,000,000 1,000 50 100,000 320 40 10,000 100 30 1,000 32 20 100 10 10 10 3.2 0 1 1 -10 0.1 0.32 -20 0.01 0.1 I dB = 10 log 10 ( ----- ) I0 Gain • Power … watt • Intensity… watt / cm2 • Loudness or strength • Decibel notation …

  6. Reflection Absorption Frequency Penetration Scattering Frequency Vs Penetration 頻率與穿透力的關係 結果: 超音波頻率提升,穿透力卻下降

  7. Frequency Vs Resolution 頻率與解像度的關係 Higher Frequency can Reflect smaller objects 超音波頻率提升解像度也會提升

  8. Elevation Axis Lateral Resolution Spatial Resolution Acoustic lance Matching Layer Crystal Absorbing material Frequency Transmit Signal process Focusing Steering Channel ….

  9. Strong reflection Resolution Contrast Resolution Compress Dynamic Range Expand Soft Tissue Weak Compress reflection Visual light Acoustic Signal

  10. Beamfomer Transducer

  11. Beamfomer

  12. Signal process

  13. Anatomy Information Management B Mode Color Flow Image Doppler Spectrum Function Viability

  14. Signal process / Control TGC Dynamic Range Focus Depth Gain

More Related