著者

宮前 博

出版者

日本眼光学学会

雑誌

視覚の科学 (ISSN:09168273)

巻号頁・発行日

vol.33, no.4, pp.133-137, 2012 (Released:2019-11-22)

参考文献数

1

被引用文献数

1

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眼内レンズ(IOL)への応用が近年著しい回折レンズの原理について解説する。回折型のIOLは,通常の屈折レンズの片面に多数の同心円状の薄い微小プリズムからなる回折面を張り付けたものである。回折面に入射した光線は,射出するときには入射光線と同じ方向に進む光線とほんのわずかに屈折する光線に分かれる。そのため回折レンズ全体は二つの焦点位置が近い二焦点レンズとなる。このとき,隣り合う微小プリズムを射出する光の位相差を制御する必要がある。また,波長によって2本の射出光線へのエネルギーの分配が変わるが,これは微小プリズム材の屈折率の分散と回折現象そのものの分散が異なることによる。

著者

宮前 博

出版者

日本眼光学学会

雑誌

視覚の科学 (ISSN:09168273)

巻号頁・発行日

vol.33, no.1, pp.8-13, 2012 (Released:2019-11-22)

参考文献数

4

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ゼルニケ多項式による波面収差の展開とその正規直交化プロセスについて述べる。ゼルニケ多項式を用いると任意の波面収差について展開係数を求めることが容易であり,例えば各収差成分が波面収差のRMS(root mean square)値にどれほど寄与しているかが即座にわかる。また二次元平面ベクトルとのアナロジーを用いて,ゼルニケ多項式を用いるメリットを説明する。ゼルニケ多項式にはフリンジオーダーという並べ方があり,低次項がそのままザイデル収差に対応するなど応用上便利である。

著者

吉田 哲也 五十嵐 敏文 朝倉 國臣 宮前 博子 彌富 信義 橋本 晃一

出版者

一般社団法人 資源・素材学会

雑誌

資源と素材 (ISSN:09161740)

巻号頁・発行日

vol.120, no.10,11, pp.577-583, 2004 (Released:2006-05-09)

参考文献数

22

被引用文献数

1 3

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To reduce the volume of precipitates generated by the neutralization of acid mine drainage (AMD) containing high concentrations of Fe and As, ferritization of the precipitates was attempted by a two-step neutralization process in which magnesium oxide (MgO) was used as the first neutralizer and sodium hydroxide (NaOH) as the second. Batch neutralization experiments with MgO and continuous flow experiments by the two-step neutralization were conducted in laboratories and an AMD treatment plant. The results showed that the precipitates by the neutralization were magnetized in the continuous flow experiments, although there was Al and Si that prevented the generation of ferrite in the AMD. This indicates that ferrite was formed from the precipitates after removing most of the soluble Al and Si by the first neutralization. In addition, aging of the precipitates under reducing conditions and returning the aged precipitates to a ferrite tank were required to form ferrite. The molar ratio of As to Fe in the precipitates reached a constant value at pH>3.5. This suggests the coprecipitation of As and Fe.

著者

吉田 哲也 五十嵐 敏文 朝倉 國臣 宮前 博子 彌富 信義 橋本 晃一

出版者

一般社団法人 資源・素材学会

雑誌

資源と素材 (ISSN:09161740)

巻号頁・発行日

vol.120, no.10,11, pp.577-583, 2004 (Released:2006-05-09)

参考文献数

22

被引用文献数

1 3

---

To reduce the volume of precipitates generated by the neutralization of acid mine drainage (AMD) containing high concentrations of Fe and As, ferritization of the precipitates was attempted by a two-step neutralization process in which magnesium oxide (MgO) was used as the first neutralizer and sodium hydroxide (NaOH) as the second. Batch neutralization experiments with MgO and continuous flow experiments by the two-step neutralization were conducted in laboratories and an AMD treatment plant. The results showed that the precipitates by the neutralization were magnetized in the continuous flow experiments, although there was Al and Si that prevented the generation of ferrite in the AMD. This indicates that ferrite was formed from the precipitates after removing most of the soluble Al and Si by the first neutralization. In addition, aging of the precipitates under reducing conditions and returning the aged precipitates to a ferrite tank were required to form ferrite. The molar ratio of As to Fe in the precipitates reached a constant value at pH>3.5. This suggests the coprecipitation of As and Fe.