EDUARDO CESARNight vision video cameras, of the kind shown in war movie scenes, when soldiers, generally from the U.S. Army, invade enemy lines at night, guided by such equipment, are considered highly restricted technology because they are used for military purposes. U.S. manufacturers encounter great difficulties in exporting products that exploit all the potential of this technology, which is also useful for property security, medicine and to check product quality. This kind of equipment, which is difficult to import, may become available in the Brazilian market within six months, when Optovac, a small company located in the town of Osasco, in São Paulo’s Metropolitan Region, concludes the development of an infrared image camera.
The company specializes in the manufacturing of high-performance components and optical systems, such as special aspherical lens (for some applications, such as microscopes and magnifying glasses, these lens are more efficient than the traditional spherical lens), microscopes, objective lens and now, night vision cameras. Unlike conventional cameras, which capture the image in front of the electromagnetic spectrum visible to the human eye, the equipment developed by Optovac is a camera that detects electromagnetic radiation in the infrared spectrum. This allows for images to be obtained by means of the discrimination of tiny temperature differences between the objects and the medium they are found in.
“Everything in nature that is at a higher temperature than absolute zero [-273°C] emits electromagnetic radiation”, explains physicist Sérgio Nobre, managing partner of Optovac. “In a totally dark environment, the camera we designed generates images of a person from the heat radiated by that person, without the need of external illumination”. The region of the spectrum for capturing images, the wave length band which ranges from 8 to 12 microns, corresponds to low absorption of infrared radiation. At a temperature of 36ºC, the human body normally emits radiation with an emission peak of around 10 microns.
The equipment manufactured by Optovac is compact – it is 11 centimeters long, 23 centimeters wide and 7 centimeters high. According to Sérgio Nobre, this first version of the camera, named “Modelo 1”, is totally functional and includes features that will be implemented in different versions of the camera scheduled to be manufactured. “We are going to use the Modelo 1 for the evaluation of new image processing software to be included in the next versions. We are also going to constantly seek miniaturization”, he says. With the exception of the sensor, a component that corresponds to the film of a conventional film camera, the equipment was entirely developed at Optovac. The equipment includes such outstanding features as the camera lens, made from germanium, a semiconductor material which is not transparent for visible light, but lets infrared radiation pass through.
The thermal imaging has many other uses. Cameras equipped with this technology can be used for security purposes and border control, by helping the night navigation of boats, airplanes and helicopters and by protecting airports and big areas. In the field of medicine and veterinary medicine, thermal imaging can be used in the diagnosis of pathological processes in human beings or animals, by detecting tiny body temperature differences produced by variations in the blood flow. This technology can also be used in industrial applications, such as the verification of overheating in the movable parts of industrial equipment, the verification of heat distribution in boilers and chemical processing flasks and in the preventive evaluation of electric power networks.
To develop its thermal camera, Optovac relied on funding provided by the Financiadora de Estudos e Projetos/Finep funding agency of the Ministry of Science and Technology. In 2007, the agency allocated R$ 2,5 million for the project, through the Programa de Subvenção Econômica à Inovação funding program. Prior to this funding, in 1999 Optovac had already obtained funds from FAPESP’s Programa Pesquisa Inovativa em Pequenas Empresas/Pipe program, for the development of specific aspherical lens (see Pesquisa FAPESP no. 88). “The funds from the Pipe program led our company to generate the embryo of our research center, which is currently run by six researchers, two of whom have doctorate degrees and two have master’s degrees”, says Sérgio Nobre.
Sensor of stars
Established in 1986, Optovac began its business activities by creating valves for high-vacuum and flow control of uranium hexafluoride used in the development of the fuel cycle of the Brazilian nuclear program. Soon afterwards, the company began to design and manufacture special equipment for universities and research centers. It recently developed and produced kits used to teach science in high schools and manufactured telescopes for amateur astronomers. Last year, the company was qualified by the Instituto Nacional de Pesquisas Espaciais/Inpe national space institute to develop and manufacture objective lenses with nine high-quality optic glass components resistant to cosmic radiation to be used in star sensors for satellites. Sensors are pointed at stars so that the satellites’ computers can accurately define the satellite’s position in outer space.
1. Optical components in injected plastic with non-spherical surfaces (nº 99/11415-8); Modality Pesquisa Inovativa na Pequena e Micro Empresa/Pipe program; Coordinator Sérgio Nobre – Optovac; Investment R$ 33.000,00 and US$ 156.236,00 (FAPESP)
2. Multi-purpose passive observation thermal image camera; Modality Subvenção Econômica à Inovação program; Coordinator Sérgio Nobre – Optovac; Investment R$ 2.510.640,00 (Finep)