Sensor

Sensor Scripts and Tutorials

---

Overview

• The first part of ISETCam uses computer graphics to model scene radiance.
• The second part uses optics and modeling of the transformation of scene radiance to sensor irradiance.
• The third stage of ISETCam simulates the encoding of light by an image sensor.

Since the 1990s, image sensors have become increasingly sophisticated. They now comprise multiple components and a variety of architectures. For example, nearly all sensors include an initial filter that regulates the general waveband (e.g., IR filters). Sensors, which are arrays of pixels, incorporate microlenses in front of the pixels. They also incorporate color filters in front of the photodetectors. There may be just one or multiple photodetectors underneath the microlenses and filters. The multiple photodetectors can be used for autofocus or for high dynamic range.

The IR filter, color filters, and photodetector parameters as part of the sensor model. The sensor model accounts for both the geometric and electrical properties of the sensor. Sophisticated calculations with the microlens, however, are grouped with the advanced optics calculations in ISET3d.

Like other fundamental ISETCam concepts, the sensor has basic functions (sensorCreate, sensorCompute, sensorSet/Get, sensorWindow, sensorPlot). A large number of sensor<TAB> functions are implemented for analyzing sensor properties along with tutorials and scripts.

Sensor overview

Sensor model

To dive deeper into the sensor structure and its computations, visit the Sensor model page.

Human visual system

For many years, we also modeled human visual encoding using portions and specialization in ISETCam. Around 2015, Dave Brainard, Joyce Farrell, and Brian Wandell decided that the many specializations of the human encoding needed their own implementation. Until about 2023, we maintained parallel repositories for ISETCam and ISETBio.

In 2023-2024 we refactored the code in the two repositories, making ISETCam the base and ISETBio a specialization that built on ISETCam. These days the way we calculate for the human specializations is by using ISETBio and including both ISETCam and ISETBio on the Matlab path.