Week 11 - SpO2 coding.....

As salam..

This week already week 11..
Sensor done !
Coding for heart rate done !
Wifi on the way....
Coding for pulse oximeter still on research...

Especially on the Arduino coding..
Actually already in month, I'm still in searching this
pulse oximeter program..
I had search in YouTube about the pulse oximeter
project. Mostly the result is displayed in waveform..
The coding mostly not share with public..
and some of are not for pulse oximeter..
but for heart rate..

I had asked my seniors that had an experienced in this
pulse oximeter. One of that I asked.. I'm explore the
coding. The coding that used is JAL program and the
measurement of pulse oximeter in this program
is same with the heart rate. So the reading for heart rate
and pulse oximeter are same.
For sure the reading of pulse oximeter is wrong here.
We know the normal reading for pulse oximeter is about
98-100.
I'm also doing my research in library which looking
on the final year report. One of is related with pulse oximeter
and that one the only used Arduino program.
The other used a PIC program but when I'm looking on
the program, it shows measurement on heart rate.

Generally, calculation SpO2 in theory is

Oxygen Saturation =  C(HbO2)/ (C(Hb) + C(HbO2) x 100%

C (Hb) = Concentration of deoxygenated hemoglobin
C (HbO2) = Concentration of oxygenated hemoglobin

The comprehension about the pulse oximeter is like below:

When the finger is placed between the light source and the light

detector, the light will pass through the finger to reach the 

detector. Part of the light will be absorbed by the finger and

the part not absorbed reaches the light detector.

The amount of light is absorbed by the finger depends on
many physical properties and these properties are used by the
pulse oximeter to calculate the oxygen saturation.

The amount of light absorbed depends on the following:

1)   Concentration of the light absorbing substance.
2)   Length of the light path in the absorbing substance
3)   Oxyhemoglobin and deoxyhemoglobin absorbs
      red and infrared light differently.

The different of absorbent of the red and infrared light
will give the different wavelength. Which the Oxy Hb is
absorbs more infrared light than red light.
For the Deoxy Hb is absorbs more red light than infrared
light. By this it can be related with the calculation in theory.
The problem here is to get in coding is a big problem
for me. Whatever it is I should find it !