10 Commandments

Question 1

1. intensities may be reported in different ways with respect to time and space

Answer 1

T

Question 2

2. measure of intensity is important for the study of bioeffects
   * SPTA is the most relevant intensity with respect to tissue heating

Answer 2

T

Question 3

3. Units of intensity w/cm2

Answer 3

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Question 4

4. SPTP intensity has the highest value and SATA intensity has the lowest value
   (peak measure is larger than average measure)

Answer 4

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Question 5

5. beam uniformity coefficient (SP/SA factor) describes the spread of beam in space
   * unitless (value of 1 or greater)

Answer 5

T

Question 6

6. duty factor describes the relationship of beam intensity with time
   * unitless (value between 0 and 1)

Answer 6

T

Question 7

7. with continuous waves the beam is always “on”
   PA and TA intensities are the same
   (SPTA = SPPA and SATA = SAPA)

Answer 7

T

Question 8

8. • pulsed and continuous waves with same SPTP (continuous waves have higher SPTA)
     * pulsed and continuous waves with same SATP (continuous waves have higher SATA)

Answer 8

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Question 9

9. temporal considerations:
   • Temporal Peak intensity (Itp) is max intensity in time
   • Im or Imax intensity is averaged over the most intense half-cycle
   • Pulse Average intensity (Ipa) is averaged only during pulse duration (“on” time only)
   • Temporal Average intensity (Ita) is averaged during PRP (both “on” and off

Answer 9

T

Question 10

10. spatial considerations:
    • Spatial Peak intensity (Isp) is the max in space
    • Spatial Average intensity (Isa) is averaged over the cross-sectional area of the beam

Answer 10

T