Project/Area Number  06650062 
Research Category 
GrantinAid for Scientific Research (C).

Research Field 
Applied optics/Quantum optical engineering

Research Institution  Osaka ElectroCommunication University 
Principal Investigator 
IKUTA Takashi Osaka ElectroCommunication Univ.Faculty of Engineering, Professor, 工学部, 教授 (20103343)

CoInvestigator(Kenkyūbuntansha) 
KISHIOKA Kiyoshi Osaka ElectroCommujnication Univ.Faculty of Enigneering, Professor, 工学部, 教授 (50109881)

Project Fiscal Year 
1994 – 1995

Project Status 
Completed(Fiscal Year 1995)

Budget Amount *help 
¥2,100,000 (Direct Cost : ¥2,100,000)
Fiscal Year 1995 : ¥600,000 (Direct Cost : ¥600,000)
Fiscal Year 1994 : ¥1,500,000 (Direct Cost : ¥1,500,000)

Keywords  Image processing / Active image processing / Modulation spectroscopy / Convolver / Weighting method / Time of stay weighting / Optimizing problem / Least mean square error criterion / 画像処理 / 能動型画像処理 / モジュレーション・スペクトロスコピー / コンボルバ / 荷重付け法 / 滞在時間型荷重付け / 最適問題 / 最小二乗誤差規範 
Research Abstract 
Previously, we have proposed a concept of the active (modulation) image processing method which is an extension of well known modulation spectroscopy, for 2dimensional images. For both the active image processing and the modulation spectroscopy, integration operation is carried out after multiplication of a bipolar weighting funciton to observed image/signal, synchronized to the active modulation. To apply multiplication of the weighting function, two different weighting implementations are possible. First is a conventional numerical weighting, and next is a timeofstay weighting. And both weighting implementations can be used together, while such combinaion results in different signal to noise {S/N} ratio for the processed images. In the present study, we have defined an optimizing weighting problem as to obtain optimized combination of these weighting implementations resulting maximum S/N ratio. At the first stage {1994} of the study, theoretical analysis has been aimed to the case in which the noise power is independent on the modulation or the signal. And we have got an exact solution using Schwarz's inequality. Namely, we obtain maximum S/N ratio when only the timeofstay weighting is implemented in this simple case. In the next stage {1995}, we have applied a computer simulation of both weighting implementations to evaluate the S/N ratio under more complicated cases in which the noise power is dependent on the modulation or the signal. At same time we have continued to get an exact solution of such optimizing problem. And then we have successfully obtain an exact solution for such complicated case. This is `To implement the numerical weighting, as the noise power after the implementation of the numerical weighing is independent on the modulation', and then `To apply the timeof stay weighting to satisfy the whole weighting function'. This important result has been clearly well confirmed by the previous simulation.
