Jun 25

Patent: Integrated Light Field Sensor on a Chip

Patent: Integrated Light Field Sensor on a Chip (Figure by Kim 2017, modified by www.lightfield-forum.com) Current light field sensors typically consist of an imaging sensor and a separate microlens array, both of which are assembled into an optical system. While this allows the use of common CCD- or CMOS sensors, it may also introduce some issues where extreme precision is needed for optimal imaging conditions, e.g. with microlenses of micrometer-range focal lengths. A mismatch of these separately fabricated elements can affect image quality.
A new patent application by Jong Eun Kim at SK hynix (Korea) aims to solve these potential issues: The patent application details a novel light field imaging device where the microlens array is formed on top of the imaging sensor. Continue reading

Mar 13

New Apple Patent for Light Field Camera …in Manufacturing Processes

New Apple Patent for Light Field Camera ...in Manufacturing Processes (Picture: Apple) Light field imaging has captured the mind of many technology enthusiasts and imaging pioneers, and there have been rumours of light field cameras in future iPhones or Android smartphones.
Now a new patent has surfaced that shows Apple is still interested in light field cameras. The twist is, the proposed “plenoptic” (a.k.a. light field) camera system is intended to aid robots in the manufacturing process. Continue reading

Aug 17

Ricoh Patents Dynamically Adjustable Multimode Lightfield Imaging System

Ricoh Patents Dynamically Adjustable Multimode Lightfield Imaging System (Fig. modified from Shroff & Berkner 2014) Ricoh researchers Sapna A. Shroff and Kathrin Berkner have lodged a patent application that describes a new way to dynamically adjust the recording parameters of a light field camera. The US Patent and Trademark Office has recently published patent application US20140192255, entitled “Dynamic Adjustment of Multimode Lightfield Imaging System Using Exposure Condition and Filter Position”, in which the authors use a non-homogeneous filter module at the pupil plane of a multimode imaging system, which can be moved and thus used to modify the imaging system’s exposure conditions. Continue reading

Aug 05

Samsung Patents Modified Light Field Sensor with Monochrome Sub-Images

Fig. 6 from Samsung's patent application shows three exemplary colour-filtered light rays passing through microlenses to create monochrome sub-images (Fig. modified from Lee et al., 2014). In order to record colour images, camera sensors typically use a colour filter array consisting of red, green, and blue filters on top of the light-intensity sensing sub-pixels. After recording each sub-pixel’s light intensity, the so-called “demosaic” process combines four monochrome sub-pixels (2x red, 2x green, 1x blue) into a single pixel containing RGB colour information.
In microlens-based light field cameras, this “demosaic” job may result in a blur effect around the boundaries of objects in the final image.
Image Sensors World found a patent application by Samsung which can solve this blur-problem: In the patent application entitled “Photographing device and photographing method for taking picture by using a plurality of microlenses”, authors Tae-Hee Lee et al. propose moving the colour filter in front of the microlenses (instead of having them behind the microlenses), creating single-colour sub-images. Continue reading

Jul 15

Visera Patents Integrated Light Field Sensor Manufacturing Process

Fig. 3 from the patent application shows a schematic of a light field camera including the proposed single-piece light field sensor (picture modified from Wang et al., 2014) Light field technology is making its way into the mainstream, but the production and assembly of some of its components has not quite reached an efficient scale of mass production.
A typical light field sensor consists of an ordinary image sensor and a microlens array (MLA) or printed mask.
In the assembly of light field sensors, one of the most vital processes is the precise adjustment of the MLA‘s position on the sensor. This adjustment is required for every individual sensor and can thus take up a long time. Since the MLA is usually positioned using screws or springs, physical impact on the light field camera may displace the light field sensor’s layers.

With patent application US 20140183334 A1 “Image sensor for light field device and manufacturing method thereof“, recently discovered by Image Sensors World, Visera Technologies is aiming for an integrated manufacturing method for light field sensors: Authors Wei-Ko Wang and colleagues propose a system where two layers of microlenses (and an intermediate space layer) are formed directly on the image sensor using semiconductor processes. Continue reading