Which components detect the light emitted by the diodes in a pulse oximeter?

Which components detect the light emitted by the diodes in a pulse oximeter?

• A. Diodes (Infrared Diode And Red Diode)
• B. Photocells (Infrared Photocell And Red Photocell)
• C. Electronic Processor
• D. Display

Answer: (B)

The key concept is that after the tissue is illuminated by two wavelengths, the device must sense how much light actually passes through. The detectors convert that light into an electrical signal that the electronics can analyze. Photocells respond to light by producing a current that depends on light intensity, and having one for each wavelength (red and infrared) lets the system compare how each wavelength is absorbed. This is what lets the oximeter determine oxygen saturation. The diodes are the light sources, not detectors, while the processor analyzes the signals and the display shows the results.

The key concept is that after the tissue is illuminated by two wavelengths, the device must sense how much light actually passes through. The detectors convert that light into an electrical signal that the electronics can analyze. Photocells respond to light by producing a current that depends on light intensity, and having one for each wavelength (red and infrared) lets the system compare how each wavelength is absorbed. This is what lets the oximeter determine oxygen saturation. The diodes are the light sources, not detectors, while the processor analyzes the signals and the display shows the results.