Pulse width/duration is measured in which unit?

Pulse width/duration is measured in which unit?

• A. Milliseconds (ms)
• B. Seconds
• C. Nanoseconds
• D. Minutes

Answer: (A)

Pulse width, or duration, is the length of time each laser pulse lasts. In laser hair removal, this duration is measured in milliseconds because the hair follicle responds best to pulses that occur over a few milliseconds. This timing allows enough energy to be absorbed by the hair’s pigment and heat the follicle without spreading heat too much to surrounding tissue. Nanoseconds are far too short for effective follicle heating in typical hair removal settings, while seconds or minutes would deliver energy too slowly and cause excessive heating. So, milliseconds is the practical and effective unit for pulse width. Typical pulse widths in practice range from several to a few dozen milliseconds.

Pulse width, or duration, is the length of time each laser pulse lasts. In laser hair removal, this duration is measured in milliseconds because the hair follicle responds best to pulses that occur over a few milliseconds. This timing allows enough energy to be absorbed by the hair’s pigment and heat the follicle without spreading heat too much to surrounding tissue. Nanoseconds are far too short for effective follicle heating in typical hair removal settings, while seconds or minutes would deliver energy too slowly and cause excessive heating. So, milliseconds is the practical and effective unit for pulse width. Typical pulse widths in practice range from several to a few dozen milliseconds.