Plenoptic photography, also known as integral technology or lightfield technology, consist of recording multiple perspectives of a sample or 3D scene using an array of lenses or microlenses that is placed somewhere between the scene and an image sensor. Thus, the 3D information, that is the information of the trajectories of the rays that come from the scene, is stored in an array of 2D microimages.
During the last century, there has been a growing interest in researching and implementing effective technologies for the capture, processing and visualization of 3D images. This interest is evidenced by the publication of a large number of papers in scientific journals of high impact, as well as by the investment effort by public organizations and private industrial entities. The applications of this technology range from entertainment, manufacturing and quality control, security and defense, and increasingly biomedical applications.
Among the different alternative technologies for 3D imaging and display, integral photography provides a very promising approach due to its ability to work with polychromatic scenes and with incoherent illumination or environmental light for scenarios from the macroscale to the microscale.
Plenoptic imaging has some challenges that need to be solved. The position in the optical path where the microlens array is located, the distribution of the 3D information among the microimages and how the size of these microimages is limited are key aspects.
DOIT® (Digital Optical Imaging Technology) is based on a paradigm shift in the capture of the plenoptic information. Instead of capturing the information near the image plane (conventional techniques do so), our design captures in the Fourier plane. In this way, the orthographic perspectives are obtained directly, without the need for any digital processing. Besides, the requirement of using small microlenses is also avoided, which eludes the wave-particle duality that limits the resolution in conventional plenoptic modalities.
< lightfield_benefits >
Why using lightfield for microscopy?
For 15 years, the implementation of lightfield microscopy (also called plenoptic or integral microscopy) has been proposed. Lightfield microscopy has the capacity to record the 3D information of thick samples without the need to perform more than a single shot. By capturing different perspectives and using the appropriate algorithms, it is possible to perform in-depth reconstruction (focusing on different planes) and calculate a depth map of the distinguishable parts across the width and length of the sample.