Three years ago, Indigo Systems launched its Omega camera line, which to this day remains one of the world's smallest, lightest, lowest powered infrared cameras. The concept of a miniature thermal imager has proven very successful, and thousands of cores have been employed in a number of portable applications, including firefighting, unmanned vehicles, and handheld imagers. A common thread to these high-volume markets is their elasticity-lowering cost substantially enhances demand. Hence the motivation behind Indigo’s newest miniature camera, Photon. Photon is a product family of small and mid-format sensor engines (160x128, 320x128, 320x256) specifically optimized for low cost and high volume. While it shares many of Omega's positive benefits, including remarkably small size, weight, and power, several aspects of the design contribute to it being more affordable than its fore-runner even with four times as many pixels. This paper compares the Photon design to the Omega with particular focus on those aspects affecting manufacturability and cost.
Indigo’s emergence as a production source of uncooled microbolometers was reported in the SPIE proceeding in 2003. With now over a year of modest volume production history on the small-format FPAs, the details of the production experiences are reported. Progress on the mid-format arrays is discussed as are the efforts towards large-format, small pixel devices. Also discussed is the status of the production ramp that will lead to the supply of uncooled FPAs into the automotive market.
Thermal weapon sights have been used by the U.S. military for decades. More recently, there has been a growing interest in infrared imagers for paramilitary and civilian applications such as law-enforcement and homeland defense. However, traditional weapon sights are not always ideal products for these applications because they do not typically have form-factor or features allowing them to be readily employed as general-purpose imagers off the weapon. Simply stated, most law-enforcement agencies cannot afford a dedicated sniper scope. Instead, this market demands a thermal imager that can be employed in a variety of situations, both weapon-mounted and handheld. Described herein is a new infrared sight that provides this multi-use capability. Based around the Omega imaging core developed by Indigo Systems, this lightweight system employs a unique housing design that mounts to a weapon rail or tripod or is held comfortably in one hand for use as a short-range “pocket scope”. Key aspects of the design are discussed, with particular focus on ergonomics, human factors, and advanced features that enhance its utility in a multi-use role.
While microbolometers have been in production for several years, the number of companies producing them is quite small. Indigo Systems has entered into the development and production of VOx based microbolometers, at its Goleta facility. Through the investment of significant capital, Indigo has established a high volume production facility based on the silicon industry model. The 6-inch, cassette-to-cassette, highly automated facility is capable of yielding hundreds of thousands of die per year. Discussed in the paper will be the design and layout of the facility, performance of the devices, as well as yield, trend and throughput data.
By providing visibility through smoke and absolute darkness, thermal imaging has the potential to radically improve the effectiveness and safety of the modern firefighter. Some of the roles of thermal imaging are assisting in detection of victims; navigating through dark, smoke-filled structures; detecting indications of imminent flash-over/roll-over; identifying and attacking the seat and extension of a fire; and surveying for lingering hot spots after a fire is nearly extinguished. In many respects, thermal imaging is ideally suited for these functions. However, firefighting applications present the infrared community some unique and challenging design constraints, not the least of which is an operating environment that is in some ways more harsh than most aerospace applications. While many previous papers have described the benefits of thermal imaging for firefighters, this paper describes several specific engineering challenges of this application. These include large ambient temperature range, rapidly changing scene dynamics, extreme demands on AGC, and large dynamic range requirements. This paper describes these and other challenges in detail and explains how they were addressed and overcome in the design of <i>Evolution 5000</i>, a state-of-the-art thermal imager designed and manufactured by Mine Safety Appliances (MSA) using Indigo System’s Omega miniature uncooled camera core.
Miniature unmanned aerial vehicles (UAVs) are a category of aircraft small enough to be transported, launched, operated, and retrieved by a crew of one or two. The concept is not new, having been in limited use by the U.S. military over the past fifteen years, but interest in potential applications is growing as size and cost of the vehicles come down. An application that is particularly significant to the military and law-enforcement agencies is remote reconnaissance, with one or more onboard sensors transmitting data back to the operator(s) in real time. Typically, a miniature UAV is capable of flying a pre-programmed route autonomously, with manual override as an option. At the conclusion of the mission, the vehicle returns for landing, after which it can be quickly disassembled and stowed until its next use. Thermal imaging extends the utility of miniature UAVs to operations in complete darkness and limited visibility, but historically thermal imagers have been too large and heavy for this application. That changed in 1999 with the introduction of Indigo System's Alpha<sup>TM</sup> camera, which established a new class of thermal imaging product termed the infrared "microsensor". Substantially smaller and lighter than any other infrared imaging product available at the time, Alpha<sup>TM</sup>was the first camera that could be readily packaged into the nose of a miniature UAV. Its low power consumption was also a key enabling feature. Building upon the success of Alpha<sup>TM</sup>, Indigo then took the microsensor class a step further with its Omega<sup>TM</sup> camera, which broke all the records established by Alpha<sup>TM</sup> for small size, weight, and power. Omega<sup>TM</sup> has been successfully integrated into several miniature UAVs, including AeroVironment's Pointer and Raven, as well as the Snake Eye UAV manufactured by BAI Aerosystems. Aspects of the Omega<sup>TM</sup> design that have led to its utility on these and other platforms are described, and future prospects for even smaller microsensors are discussed.
The proliferation of small infrared cameras in high-volume commercial applications (e.g. firefighting, law-enforcement, and automotive) presents a tremendous opportunity for truly low-cost military micro-sensors. Indigo Systems Corporation's UL3 OmegaTM camera is a commercial off-the-shelf (COTS) thermal imager that offers ultra-small size, light weight, and low power. It employs a 164×120 microbolometer focal plane array (FPA) and is currently entering full-scale production. Furthermore, a 324×240 upgrade is in development. While aimed primarily at the commercial market, small size and low-power consumption make UL3 well-suited for other applications, including miniature unmanned aerial vehicles (UAVs) weapon-sights, and unattended ground sensors (UGS). This paper focuses on the key features of the UL3 family of miniature IR cameras and their utility in soldier systems.
When it was first introduced two years ago, Indigo Systems Corporation's UL3 Alpha, a miniature uncooled infrared camera, set new standards for ultra-low size, weight and power within the thermal imaging industry. Now Omega, the next generation in Indigo's UL3 product line, takes advantage of novel algorithms and packaging concepts to further reduce size, weight, and power while still improving performance. These qualities make Omega an ideal candidate for many commercial and military applications, including fire-fighting, law enforcement, industrial inspection, remote surveillance, miniature unmanned aerial vehicles (UAVs), unmanned ground vehicles (UGV), and numerous other possibilities. This paper describes the design, performance and salient features of the Omega camera. Current and future applications of the UL3 product line are also discussed.
Portable thermal imagers are being utilized with great success in many new and emerging applications, and the law enforcement field in particular is benefiting from thermal imagery. It is quickly becoming common practice for enforcement agencies to apply night-vision technology in such activities as search and rescue, surveillance and stakeout, and suspect pursuit. Thermal cameras, however, do not typically provide an intrinsic means for video recording or for visible imaging. Such capabilities could significantly expand and improve the uses of thermal imaging by law enforcement personnel. For example, surveying the scene of a crime or traffic accident with a thermal sensor offers potential for revealing and documenting clues that otherwise go unnoticed. This paper presents a system that integrates an IR micro-camera with a visible camcorder. The system can display and record live visible and thermal imagery and also capture single-frame snapshots on removable media. This paper also explores the utility of such an integrated camera in various law enforcement scenarios.
This paper describes an unattended surveillance system that is used to monitor border crossings, remote airfields, choke points, and any other remote area not suitable for continuous human presence. The system employs intelligent acoustic/seismic unattended ground sensors, two-way radio communication, and a low light video camera. The acoustic/seismic sensors provide long-range target detection, target classification, and angular bearing to the target. The camera is cued by the acoustic/seismic sensors and takes a picture of the target for visual confirmation. All information, including the picture, is transmitted via radio to a monitoring post.
Infrared sensors have advanced in performance and reduced in price to new and unsurpassed levels. Significant advancements in uncooled technology have recently enabled the notion of an expendable infrared sensor. Further performance and producibility improvements are still required such as the elimination of the thermal electric cooler and shutter, as well as high levels of signal processing integration. Additionally, the economy of scale associated with very large volumes will be realized as specific, enabling price points are achieved. Specific cost objectives and enabling technology requirements are discussed.
Integrated two-color detector arrays offer significant system advantages (over separate arrays for each color) where two-color information is required. Using a single array with co-located spectral band sensitivities guarantees perfect pixel registration between the two different spectral band images. These two-color IR detectors can be made in HgCdTe using a pair of back-to-back-diodes incorporated in a triple-layer heterojunction (TLHJ). Use of HgCdTe allows any combination of bands between SWIR and LWIR. TLHJs can be operated in either a sequential or simultaneous mode by leaving the layer common to the two diodes floating or by contacting it. The effect of the choice of spectral bands on the meaning of sequential and simultaneous operation is discussed. State-of-the-art trend line performance for each spectral band of a TLHJ has been demonstrated using an all-LPE HgCdTe technology at SBRC. Mean MWIR R<SUB>r</SUB>A of 2 X 10<SUP>7</SUP> (Omega) -cm<SUP>2</SUP> and LWIR of 1.6 X 10<SUP>3</SUP> (Omega) -cm<SUP>2</SUP> have been shown. Quantum efficiencies are typical of trend line PV HgCdTe. Very high quality imaging has been demonstrated using 64 X 64 sensor chip assemblies in a sequential mode incorporating the above TLHJs. Simultaneous detectors have been made in miniarrays and test structures of various size unit cells. 128 X 128 simultaneous arrays are under study. Imaging and test results (performance and uniformity) for each band are comparable to state-of-the-art single-color HgCdTe arrays.
This paper describes a staring Platinum Silicide (PtSi) medium wave infrared (MWIR) camera. The sensor is configured with a 244 x 400 hybrid focal plane array (HFPA), which has a 24 x 24 sq micron unit cell and an 84-percent fill factor. The PtSi HFPA exhibits high sensitivity with a single pixel NE-Delta-T less than 0.09 C at F/2.0 at 60 Hz. The HFPA performance characteristics, such as dc uniformity, signal responsivity, noise, and NE-Delta-T, are reviewed. The camera containing the HFPA is divided into two units: a camera head and camera processor. The camera head operates at a 60 Hz frame rate generating two 3.6 MHz video outputs. The camera processor converts these two outputs into RS-170 video. Nonuniformity correction and video reformatting are performed in the processor. The system architecture, operation, and system performance are described.