Primary Design: Visual Indicator
|
Specification |
Quantity |
|
Accurate |
Pulse response time +/- 1 second |
|
Water Resistant |
Up to 10 meters |
|
Temperature Independent |
Functions between 0oF and 150oF |
|
Inexpensive |
Cost is less than $25 per unit |
|
Portable |
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
Concept:
- Pulse will pass vibrations through both diaphragms
- Amplified enough to display Korotkoff sounds