Aspectra Mini (App on Google-Play) is the base application in Aspectra system.

The Android device, with additional low cost spectrometer, can be used to observe the spectrum of light. Spectrum is shown as intensity plot. Every plot can be saved for future analyze with another Application: Aspectra-Viewer

 Live-view Activity

User actions in Activity:


        switch to the Config-activity


        actual plot will be saved in file-system.


        switch to Aspectra-Viewer application

The structure of the view

The screen is divided into two regions:

Left: Camera preview, Right: intensity plot.

In Camera-preview,

The green lines help in defining Area of Interest.

The red lines, define the Area Of Interest:

        M lines in Y (intensity) axis,

        N (wave length) axis, pixels from Start-Pixel to End-pixel.

Distance between both red lines defines how many of pixels are taken to calculate the average Y value.

Wave-length axis can be vertical or horizontal. it depends on the build of spectroscope.

Actual screenshot show the portrait orientation of spectrum. Portrait/Landscape orientation of spectrum should be defined in preferences.

Intensity plot-Area

shows the values of Intensity, from StartX to EndX

Y Value is the Average of M pixels in intensity-axis of camera preview. 

 Config-view Activity

User actions in Activity:

camera-preview -> touch:

        back to LiveViewActivity


        modify the value

The positions of sliders define the borders of the Area Of Interest.

Sliders: WidthStart, WidthEnd,  HeightStart

(values in percent of the whole camera preview)

can be incremented by one.

Slider: Amount of summed Y lines (value in Lines)

        can be defined: 1, 2, 4, 8, 16, 32, 64.

Every Value is saved for future use in Application-preferencies 

Preferences Activity

The following applications' preferences can be edited:

The name of the folder for saving plots,

The extension of spectrum-file's name

The orientation of the spectrograph depends on the construction of the spectrograph, from the angle between the optical-grating and camera-orientation.

For the mini-spectrograph, shown  here, the orientation is portrait mode.

The mirroring: most of the Android-devices needs the mirroring of the data


 App release log
Version Date Notes
1.0.1 18.02.2017 first release
1.0.2 15.03.2017 published on Google Play
1.0.3  20.04.2017 fixed camera not present or not responding 
1.0.4 30.05.2017 fixing some bugs reported from users
1.0.5 07.06.2017 fixing bugs reported from users