Energy Falling on an Infrared Sensor

A Fresnel lens can focus infrared energy onto a sensor. These lenses transmit most of the infrared energy, but some is still absorbed by the lens. In this application, the energy transmitted by the lens was calculated. The transmission of the lens was traced from published data by Dagra.

View IR Sensor example.

White Light Emitting Diode Plotted on Tristimulus Curves

In LEDs, white light is created by combining several colours on a single chip. In this example, "warm" and "daylight" LEDs are plotted on the CIE tristimulus curves to show their colour composition. Dagra was used to trace the spectra from the LED data-sheet and the tristimulus curves.

View LED example.

Atmospheric CO₂

This video example demonstrates Dagra's new screen shot tool to extract data points from a graph window. The mean carbon dioxide level was obtained from the Wikipedia article on Carbon dioxide in the Earth's atmosphere.

View Atmospheric CO₂ example.

Digitze PDF Graphs

A great deal of design data is presented graphically in Adobe Reader PDF (portable document format) files. This example shows how numerical values can be quickly digitized from graphs in PDF files.

View Digitize PDF graphs example.

Linear Interpolation with Excel

Most analysis packages include functions for linear interpolation that are ideal for working with data exported by Dagra. Unfortunately, Microsoft Excel doesn't. This short example demonstrates a simple method for linear interpolation in Excel.

View Excel Linear Interpolation example.