• Journal of Institute of Control, Robotics and Systems
• /
• v.15 no.3
• /
• pp.265-272
• /
• 2009

In this paper, a simple optical method that uses an infrared(IR) cut filter is proposed to minimize variation of eye image by external infrared(IR) sources in a video based head mounted eye tracking system that is used in the field of sports. For this, the IR cut filter is attached to a head mount of the eye tracking system, and the camera with an IR LED is located between the IR cut filter and eye. In this structure, external IR is blocked by the IR cut filter, and the IR intensity on the eye can be controlled by the IR LED. Therefore, the illumination condition of the camera to capture the eye can be stable without being affected by external IR illuminations. To verify the proposed idea, variation of the eye image and intensity of the IR with/without the IR cut filter is measured under various illumination conditions. The measured data show that the IR cut filter method can block external IR effectively, and complex pupil detection algorithms can be replaced by a simple binarized method.

• The Journal of the Korea Contents Association
• /
• v.11 no.5
• /
• pp.205-215
• /
• 2011

Films are sensitive to ultraviolet rays and in contrast, digital camera sensors are extremely sensitive to infrared rays due to the differences in spectral characteristics. As a result, all digital cameras that use CCD or CMOS are equipped with IR Cut-Off Filter on the overall sensor. Complete block out of infrared rays is ideal, but the actual experiment results showed that infrared rays were not being blocked out completely. Infrared permeability was also different for each camera. Therefore, this study aims to analyze the effect of the minute quantities of infrared rays, which get transmitted due to mechanical properties of IR Cut-Off Filters that are installed on digital cameras, on digital picture images. The results obtained by carrying out a comparative analysis of a UV Filter (infrared transmitting state) and a UV-IR Filter (infrared blocked out state) are as follows. It was confirmed that the minute quantities of infrared rays do affect dynamic range and resolution to some extent, despite the little or no difference in noise and color reproduction.

• Transactions on Electrical and Electronic Materials
• /
• v.18 no.6
• /
• pp.341-344
• /
• 2017

Infrared (IR) filters were developed to implement integrated three-dimensional (3D) image sensors that are capable of obtaining both color image and depth information at the same time. The combination of light filters applicable to the 3D image sensor is composed of a modified IR cut filter mounted on the objective lens module and on-chip filters such as IR pass filters and color filters. The IR cut filters were fabricated by inorganic $SiO_2/TiO_2$ multilayered thin-film deposition using RF magnetron sputtering. On-chip IR pass filters were synthetized by dissolving various pigments and dyes in organic solvents and by subsequent patterning with photolithography. The fabrication process of the filters is fairly compatible with the complementary metal oxide semiconductor (CMOS) process. Thus, the IR cut filter and IR pass filter combined with conventional color filters are considered successfully applicable to 3D image sensors.

• Proceedings of the Optical Society of Korea Conference
• /
• 2006.07a
• /
• pp.429-430
• /
• 2006

• Korean Journal of Optics and Photonics
• /
• v.35 no.1
• /
• pp.24-29
• /
• 2024

We propose a hyperbolic metastructure based on a nanopatterned metal (Ag)-dielectric (PDMS) multilayer and report on its performance in an infrared (IR) cut-off filter for imaging devices. By optimizing the size of the square-shaped Ag nanopattern and the thickness of PDMS surrounding the Ag nanopattern, the proposed IR cut-off filter blocks 99% of light in the 0.70-1.01 ㎛ wavelength band while maintaining a high transmittance of over 94% in the visible region. Here, the cut-off wavelength band starts at a region above the epsilon-near-zero wavelength of the hyperbolic metastructure and ends at the point where plasmonic absorption appears strongly. It is observed that transmittance in the wavelength region longer than the IR cut-off band increases again due to plasmonic coupling among horizontally adjacent Ag nanopatterns. This metastructure can improve the performance of IR-blocking filters as well as allow it to be manufactured ultra-thin, which is applicable to various planar optical elements and integrated optical components.

• Korean Journal of Optics and Photonics
• /
• v.17 no.5
• /
• pp.480-486
• /
• 2006

Generally, IR cut-off filters for mobile phone is coated on the glass substrate at high temperature(above $300^{\circ}C$). In this work, we prepared IR cut-off filters on the poly(methyl methacrylate)(PMMA) substrates at low temperature(about $70^{\circ}C$ ). using the $CeO_2\;and\;SiO_2$ coatings by physical vapor deposition. The surface energies of coated and uncoated PMMA, and adhesive properties of IR cut-off filters coatings were examined using contact angle measurements. We demonstrate the improve of mobile phone optical system using these results.

• Journal of Institute of Control, Robotics and Systems
• /
• v.14 no.8
• /
• pp.767-773
• /
• 2008

This paper presents a localization system based on the use of electric compass and tracking IR light source. Digital RGB(Red, Green, Blue)signal of digital CMOS Camera is sent to CPLD which converts the color image to binary image at 30 frames per second. CMOS camera has IR filter and UV filter in front of CMOS cell. The filters cut off above 720nm light source. Binary output data of CPLD is sent to DSP that rapidly tracks the IR light source by moving Camera tilt DC motor. At a robot toward north, electric compass signals and IR light source angles which are used for calculating the data of the location system. Because geomagnetic field is linear in local position, this location system is possible. Finally, it is shown that position error is within ${\pm}1.3cm$ in this system.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2009.11a
• /
• pp.49-49
• /
• 2009

카메라 모듈용 적외선 차단 필터를 설계하고 이온빔 증착 장비를 이용한 코팅 공정 후 특성을 조사하였다. 코팅 실험에 앞서 Macleod 프로그램을 이용하여 640nm 차단 필터를 설계하였으며, 실험은 Ion-Assisted Deposition 장비를 사용하여 $TiO_2/SiO_2$ 유전층을 다층 박막으로 증착하였다. 투과도 분석에서 640nm 차단 필터는 설계 곡선과 약 8nm 이내에서 일치하였으며, 갓 성장된 박막 투과도는 400~600nm에서 약 80% 이었으며, 급속열처리 및 열처리 후 약 5% 증가된 투과도를 보였다. 표면거칠기 또한 감소하였다. 따라서 열처리로 인한 재결정화 및 결함감소에 의해 필터특성이 향상되었음을 알 수 있었다.

• Journal of the Korean Society for Precision Engineering
• /
• v.24 no.11
• /
• pp.76-83
• /
• 2007

The dark-field laser scattering system has been developed to inspect surface defects in infrared cut-off filters and then laser scattering characteristics against the defects are investigated. The qualitative analysis for the reliable and accurate detection performance is described through the correlation between incident angles of a laser and viewing ones of a camera. In this paper, reliable and important information with laser scattering is given for the surface defect inspection of IR filters. Its performance has been verified through various experiments.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2010.06a
• /
• pp.169-169
• /
• 2010

650nm 적외선 차단 필터를 Macleod 프로그램을 이용하여 설계하고, 이온보조증착(IAD) 장비를 이용하여 코팅한 후 투과도, 파장, 두께특성을 조사하였다. 차단필터의 증착물질은 $TiO_2$ (n=2.30) /$SiO_2$ (n=1.46) 을 사용하여 45층의 다층 박막으로 증착하였다. 코팅된 차단필터는 차단파장이 651 nm로써 평균 ${\pm}5$ nm 이내의 편차를 보였다. 420~630 nm 파장영역에서 평균 투과도는 89%이었으며, 투과도의 균일도는 약 2.12로써 매우 균일하였다. 투과도기 단파장 영역에서 감소된 것은 다층박막 증착 시 산소가 결핍된 것으로 판단된다.