DRAFT: This module has unpublished changes.

Primary Design: Visual Indicator









Pulse response time +/- 1 second

Water Resistant

Up to 10 meters

Temperature Independent

Functions between 0oF and 150oF


Cost is less than $25 per unit


Size and weight less than 12x6in. and 1.5kg


Technical Requirements:

  • Visual display accuracy (+/- 1 second)
  • Operating conditions (0oF – 150oF, UV/water resistant)
  • Pressure range (0mmHg to 260mmHg)
  • Size (less then 12x6 inches)
  • Weight (less then 3.5lbs)

Two membranes

First membrane: next to the skin

- stethoscope diaphragm

- Secured by a holding ring around the inside circumference and height of the jar


Second membrane: 3/16” above the first


We have many options for this layer:

- Helium balloon mylar and/or LDPE), ~1/16” below the cap

- Essentially a liquid crystal (nail polish between two layers of plastic)

- Leads to fume deposition on the cap and deceases transparency of lid

- Let the nail polish dry between the two layers of plastic, then peel the top off

-More delicate, but increases reflection and flexibility (responsiveness)

- Lay down a nail polish and glass micro bead mixture

- Use circular reflective stickers (very good contrast and responsiveness)

- Any combination of the above



- Pulse will pass vibrations through both diaphragms

- Amplified enough to display Korotkoff sounds


DRAFT: This module has unpublished changes.