Research on digital image conversion by using photon mixing

利用光子混合进行数字图像转换的研究

• 批准号: 10450023
• 负责人: TANIUCHI Tetsuo
• 金额: $ 10.3万
• 依托单位: TOHOKU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B).
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-10450023/
• 关键词: nonlinear optics; lithium niobate; sum frequency generation; difference frequency generation; terahertz; optical parametric oscillation; 光ミキシング

We have investigated a frequency conversion from infrared to visible spectrum by using a nonlinear photon mixing in nonlintear crystals. To achieve an efficient sum frequency generation (SFG), a phase matching property of LiNbO_3 crystals was studied in detail. Also, we have experimentally investigated the frequency conversion between optical waves and terahertz (THz) waves in a GaP crystal.1) Frequency conversion from infrared to visible spectrumWe have investigated the phase matching properties for SFG in LiNbO_3, MgO : LiNbO_3, and periodically poled LiNbO_3 (PPLN) crystals. In LiNbO_3 and MgO : LiNbO_3 crystals, the infrared conversion range for SFG is determined mainly by the crystal temperature. On the other hand, we can obtain widely tunable SFG in PPLN because that the quasi-phase-matching can be achieved by controlling the domain period. Infrared radiation woth 1.5-5μm can be converted to the visible in domain-controlled PPLN.We proposed a new structure of the guided-wave SFG for a digital image conversion by digitalizing the infrared image spatially.2) Frequency conversion between optical and THz waves.The frequency conversion between optical and THz waves can be possible by SFG and difference frequency generation (DFG). GaP crystal is an attractive material for the frequency conversion because of the large uonlinear optical effect and the low loss property at the THz-wave region. We have found that the collinear phase-matching was achieved by selecting the pumping wavelength at 0.98 μm for SFG and DFG interaction. We developed an optical parametric oscillator (OPO) with KTP crystal at the wavelength range of 0.98 um. Tunable THz waves were successfully generated in the range of 0.5-2.2THz by mixing a dual wavelength OPO output in GaP.

我们研究了利用非线性光子混合在非线性晶体中的红外光谱到可见光谱的频率转换。为了实现高效的和频产生，对LiNbO_3晶体的相位匹配特性进行了详细的研究。此外，我们还实验研究了光波和太赫兹（THz）波在GaP晶体中的频率转换。我们研究了SFG在LiNbO_3、MgO: LiNbO_3和周期性极化LiNbO_3 （PPLN）晶体中的相位匹配特性。在LiNbO_3和MgO: LiNbO_3晶体中，SFG的红外转换范围主要由晶体温度决定。另一方面，由于可以通过控制域周期实现准相位匹配，我们可以在PPLN中获得广泛可调谐的SFG。在域控PPLN中，可以将1.5 ~ 5μm的红外辐射转换为可见光。通过对红外图像进行空间数字化，提出了一种用于数字图像转换的导波SFG的新结构。2)光波与太赫兹波之间的频率转换。通过SFG和差频产生（DFG）可以实现光波和太赫兹波之间的频率转换。GaP晶体具有较大的非线性光学效应和太赫兹区域的低损耗特性，是一种有吸引力的变频材料。我们发现，选择0.98 μm的泵浦波长用于SFG和DFG相互作用，可以实现共线相位匹配。研制了一种波长范围为0.98 um的KTP晶体光学参量振荡器（OPO）。通过在GaP中混合双波长OPO输出，成功地产生了0.5 ~ 2.2太赫兹的可调谐太赫兹波。

项目成果

S.Souma, H.Tahkahashi, T.Taniuchi, T.Sato, and H.Ito: "Organic nonlinear optical crystal DAST growth and its device application"International Topical Workship on Contemporarp Photonic Technologies (CPT'99). Wep-10. 123-124 (1999)

S.Souma、H.Tahkahashi、T.Taniuchi、T.Sato 和 H.Ito：“有机非线性光学晶体 DAST 生长及其器件应用”当代光子技术国际专题研讨会 (CPT99)。

谷内哲夫: "非線形光ミキシングを用いた光波・テラヘルツ波変換技術"電子情報通信学会技術研究報告,レーザ・量子エレクトロニクス研究会. LQE2000・40. 13-18 (2000)

Tetsuo Taniuchi：“使用非线性光学混合的光波/太赫兹波转换技术”IEICE技术报告，激光和量子电子学研究组13-18（2000）。

M.Sato: "6.6μm generation of optical parametric oscillation using periodically poled LiNbO_3" Applied Optics. (印刷中). (1999)

M.Sato：“使用周期性极化 LiNbO_3 产生 6.6μm 光学参量振荡”（正在出版）。

J.Shikata: "Enhancement of terahertz-wave output from LiNbO_3 optical oscillators by cryogenic cooling"Optics Letters. 24・4. 202-204 (1999)

J.Shikata：“通过低温冷却增强LiNbO_3光学振荡器的太赫兹波输出”光学快报24・4（1999）。

T.Taniuchi: "Tunable terahertz-wave generation in DAST crystal with dual-wavelength KTP optical parametric oscillator"Electronics Letters. 36・16. 1414-1416 (2000)

T.Taniuchi：“使用双波长 KTP 光学参量振荡器在 DAST 晶体中产生可调谐太赫兹波”《电子快报》36・16 (2000)。