Smartphone Spectral Response at 850-1050nm Near Infrared (NIR) Region

by Chuong Tran

Question:

Dear Sir or Madam,

I am interested in some of the possible applications of the NIR enhanced smartphones that you offer and consider to purchase one. Among the models that you offer there are several iPhone variants and also some Google Nexus variants,too.  However I am note sure which variant would suit best for me.

On your homepage you compare the performance of a modified iPhone 6 Plus vs the Nexus with the result that "that Nexus 5X has a much higher spectral response in the NIR region around 1050nm".

I have the following questions:
  1. Does this statement hold true for all the iPhone versions vs. Nexus versions in general? I.e. is any Nexus always more sensitive at 1050nm than any iPhone?
  2. Are there in-series differences in NIR sensitivity between iPhone variants and between Nexus variants?
  3. What is the situation an 850nm? Is the difference between makes and models still present at these shorter wavelength?

Answer:

  • In general they’re all very similar in spectral response as shown in the Nexus 5X spectral response graph below:

Spectral Response of Typical Smartphone Imaging Sensor

  • Of the models we are offering and tested, the Nexus 5X has highest NIR sensitivity near the 1050nm range.  See YouTube demo video.  The Nexus 5 NIR sensitivity is not as high as the Nexus 5X near the 1050nm wavelength.
  • The difference is about 3% higher at 1050nm for the Nexus 5X vs. the others but about the same spectral response at 850nm among them all.
  • All iPhone sensors were similar in NIR sensitivity around 850nm.
  • We don’t have spectral curves for all of smartphones we're offering since.  it is a very time consuming process to measure the QE Spectral Response on smartphone.

 

Back to Q&A