SITIS Archives - Topic Details
Program:  SBIR
Topic Num:  A10-055 (Army)
Title:  A large field-of-view and high resolution camera in a small form factor
Research & Technical Areas:  Sensors, Electronics

Acquisition Program:  
 The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), which controls the export and import of defense-related material and services. Offerors must disclose any proposed use of foreign nationals, their country of origin, and what tasks each would accomplish in the statement of work in accordance with section 3.5.b.(7) of the solicitation.
  Objective:  Design, develop and demonstrate a small form factor camera to provide a high resolution image capture over a wide field of view to enable significantly higher detection and classification of unexploded ordnance.
  Description:  Miniaturized small and light weight cameras that have a large field-of-view (FOV) and that maintain the same image quality throughout the FOV are needed for many applications, including military, homeland defense and commercial applications. Although large FOV imaging systems have been demonstrated recently, achieving high spatial resolution and a large FOV simultaneously still remains as a challenge. Generally, the captured images in these systems suffer from distortions caused by off-axis aberrations. Alternatively, multiple images can be obtained from using an array of lenslets, each lenslet capturing a low resolution image of the scene and applying superresolution techniques to reconstruct a single high resolution image. This approach may prove good enough for some applications. Further, some of the large FOV imaging systems using mirrors and lenses may tend to be bulky and costly. In developing a large FOV camera one may derive useful hints from biological imaging systems, in particular, from the compound eyes of insects. However, compound eyes, while having a large FOV, suffer from poor image resolution. In general, image resolution in optical systems is subject to a fundamental limit of resolution known as "Abbe's diffraction limit," according to which the best resolution that can be achieved is approximately lambda/2 where lambda is the wavelength of light. The reason for the Abbe's limit in resolution stems from the fact that the evanescent light from the object, which carries the sub-lambda information of the object's features, decay exponentially as a function of distance from the object. As a result, only the propagating waves those carrying the low frequency spatial components (coarser details) are collected at the image plane. Superresolution imaging beyond Abbe’s diffraction limit can be achieved by utilizing an optical medium or ‘metamaterials’ that can either amplify or transport the decaying near-field evanescent waves that carry subwavelength features of objects. Such materials typically have one or more of their permeability or permittivity components that are negative. These metamaterials can be artificially engineered and fabricated using controlled nanofabrication techniques and offer the possibility of restoring or recovering the lost sub-lambda object features thereby making a high resolution image with little degradation. While superresoultion may perhaps be achieved by post processing of the collected images, the advent of the negative metamaterials offer for the first time the scope for developing optical components to achieve subwavelength imaging capabilities. Research also indicates the promise for metamaterials that are tunable over wide frequency ranges. This solicitation calls for the design and development of a small form factor camera to provide a wide field of view image capture with high resolution. Novel solutions that make use of the advent of new and innovative optical materials are expected to be considered to break the fundamental barrier of achieving resolution across a large FOV. One of the challenges of this topic is to design cameras that would operate over a wide wavelength range that includes but not limited to visible to near infrared (400-900nm) and short wavelength infrared (900-1700nm).

  PHASE I: Demonstrate a proof-of-concept design to fabricating a small form factor camera using novel material and lens concepts that would offer high resolution wide field of view image capture. The proof-of-concept design should take into account size, weight and power (SWaP) of such a camera keeping in view its ultimate use in soldier hand-held and robotic applications and in smart munitions. The camera should have at least 180 degree by 90 degree field of view. Trade-off studies are to be performed to arrive at the best combination of field of view, resolution and sensitivity and yet maintaining the SWaP requirements. In one of the intended applications of locating small objects of interest, it is expected that the camera could achieve superresolution wide field of view image capture at reasonable depths to detect unexploded ordnance (UXO) (1 foot nominal depth) from standoff distances of approximately 25 feet or less.
  PHASE II: Develop and demonstrate a prototype small form factor camera that will simultaneously realize wide field of view and high resolution. Demonstrate the capability to achieve the high resolution image such that the camera can track objects rapidly moving at varying ranges. The prototype should have size, weight and power (SWaP) features that are commensurate with its intended operations in a hand held or robot mounted applications. Additionally, it is envisioned that a small form factor sensor/camera can be included in smart precision tactical/protective networked munitions. Ideally, the image collection and image recognizing functions in the small form factor camera would have the SWaP features of a cell phone camera (example: size of 10x10mm and power consumption of the order of 120 mW). The camera should have at least 180 degree by 90 degree field of view and should offer subwavelength resolution in the operating wavelength ranges. The camera should operate over a wide wavelength range that includes but not limited to visible to near infrared (400-900nm) and short wavelength infrared (900-1700nm). A prototype small form factor camera shall be delivered at the end of Phase II.

  PHASE III: The high resolution small form factor camera developed under this effort will have immediate application of detection of UXOs. It will have dual use applications in all surveillance related missions. Further, it can find applications in smart precision munitions guidance and navigation as well as in target sensing. Smaller and lighter sensors with a wide field of view and high resolution in smart munitions can provide enhanced battlefield intelligence both in tactical and protective operations. Homeland Security Operations not limited to Border Patrol, airport security, Federal Emergency Management Agency and perimeter protection surveillance operations can benefit from the small, high resolution small form factor camera that can detect rapidly moving objects over a wide field of view. The camera can be mounted on robotic platforms and can acquire high resolution images from areas which would prevent human intervention such as in buildings with fire and/or those infested with biological, chemical, nuclear agents. These robots can also be deployed in operations requiring remote surveillance applications.

  References:   1. “Foveated wide field-of-view imaging system using a liquid crystal spatial light modulator,” T. Martinez, D.V. Wick and S.R. Restaino, Optics Express, vol. 8, p.555-560 (2001). 2. E. Abbe, Arch. F. Mikroskop. Anat. 9, 413 (1873).

Keywords:  Small form factor camera, wide field of view, high resolution

Questions and Answers:
Q: What defines your higher resolution?
Is it to detect a certain object at a certain distance or rated in MPixel?
A: A: The topic states looking for objects at a distance of 25 feet. The minimum spatial resolution that can be obtained at this distance, taking into account the practical limitations of the focal plane array size (i.e. # of pixels) under the constraints of size, weight, power and cost (SWAP-C) of the camera, should be included in the proposal.

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