• 제목/요약/키워드: pantoscopic angle

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안경착용자 방진마스크 착용 시 밀착계수와 착용시력에 미치는 영향 (Effects of Fit Factor and Visual Acuity of Eyeglasses Wearers when Wearing Particulate Filtering Facepiece Respirators)

  • 어원석;신창섭
    • 한국안전학회지
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    • 제35권3호
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    • pp.105-115
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    • 2020
  • This study compares the difference of fit factors (FF) and visual acuity according to masks and eyeglasses preferences for 54 participants. We the precautions and behaviors of discomfort when wearing masks of eyewear wearers. Contact lens discomfort and priority action of complaints was investigated Glasses fitting factors is Optical Center Height(OH), Vertex Distance(VD) and Pantoscopic Angle(PA). We measured those factors and expressed by the ratio of standard point and change point. Quantitative fit factor was measured by Portacount Pro+ 8038. Also, we selected to 6 exercises among 8 exercises OSHA QNFT (Quantitative Fit testing) protocol to measure the fit factors. The pass/ fail criterion of FF was set at 100. Visual acuity(VA) test chart is developed by Chunsuk Han was used, Descriptive statistics was performed. Descriptive statistics(SAS ver 9.2), it is used geometric means, Wilcoxon analysis(P=0.05) When wearing the mask preferentially, fit factor(FF) was high according to the step of glasses fitting parameter. on the other hand, when the glasses first choice, the visual acuity(VA) was high. there was no significant difference. In the case of fit factor (FF), mask first choice/ glasses first choice is OH (p=0.671/ p=0.332), VD (p=0.602/ p=0.571) and PA (p=0.549/ p=0.607). Visual acuity (VA), mask first choice/ glasses first choice is OH (p=0.753/ p=0.386), VD (p=0.815/ p=0.557) and PA (p=0.856/ p=0.562). The workers of workplace and office chose glasses but occupational health workers and students chose mask. In case of discomforts, it was suggested to remove the mask and tolerate discomforts. The main discomforts and usual action of lens were dryness, hyperemia, foreign body sensation, ophthalmodynia, decreased vision and glasses wearing. Therefore, it is necessary to develop a mask wearing method education program considering glasses fitting and develop a hybrid model that minimizes inconvenience when wearing glasses and a mask at the same time.

안면부 여과식 방진 마스크와 안경 동시 착용 시 상호 영향 (The Effects of Interrelationship after Wearing between Respirators and Glasses Simultaneously)

  • 어원석;신창섭
    • 한국안전학회지
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    • 제33권1호
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    • pp.47-53
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    • 2018
  • This study compares the interrelation of fit factor(FF) and visual acuity test by the order of wearing preference between Particulate filtering face piece respirators(PFFR) and glasses for 54 participants. Glasses fitting factors is Optical Center Height(OH), Vertex Distance(VD) and Pantoscopic Angle(PA) or Visual acuity. We measured those factors and expressed by the ratio of standard point and change point. Quantitative fit factor was measured by Portacount Pro+ 8038 and compared the result of preference of wearing order between respirators and glasses. Also, we selected to 6 exercises among 8 exercises OSHA QNFT (Quantitative Fit testing) protocol to measure the fit factors. The pass/ fail criterion of FF was set at 100. Visual acuity test chart is developed by Chunsuk Han was used, Descriptive statistics was performed. Descriptive statistics(SAS ver 9.2), it is used geometric means, Wilcoxon analysis, peason correlation(P=0.05) Fit factor was increased when the respirator was worn before wearing the glasses(p=0.000) and decreased for visual acuity(p=0.000) The negative correlation was showed between OH and Overall fit factor(r=-0.409, p=0.002). Among 54 participants, 11 participants(20.3%) were worn respirator before wearing glasses and 1 participant(1.9%) was worn glasses before wearing respirator. The overall fit test showed the higher level was investigated for the group of participants wearing respirator before wearing glasses in 6 exercises. Also, overall fit factor were increased when participants wore glasses prior to respirator(16.6) to respirator prior to glasses(36.6). Visual acuity were increased when participants wore respirator prior to glasses(93.8) to glasses prior to respirator(106.0). Finally, comparison result of overall fit factor and visual acuity were glasses first choice from mask first choice. The results showed that higher overall fit factor was investigate when the participants wore the respirator prior to glassess at all. The results implied that it is important to maintain the overall fit factor and visual acuity according to the consideration of OH for glasses fitting when worker wore respirator and glasses at the same time.

방독면 안경 개발 (Development of Gas-mask Spectacles)

  • 이정영;박정식;장우영
    • 한국안광학회지
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    • 제13권4호
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    • pp.9-12
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    • 2008
  • 목적: 현재의 방독면은 안경을 착용하는 사람들에게는 매우 불편한 구조로 되어 있다. 이를 개선하여 군인이나 소방관들이 자신을 보호하고 인명을 구조하는데 도움이 되도록 하였다. 방법: 외면렌즈와 내면의 시력보정용 렌즈의 2중 구조로 되어 있는 것을 아크릴 프레임을 방독면에 부착하는 단일 구조로 변경하고 실리콘 차단제를 이용하여 렌즈와 프레임 사이를 밀폐하여 가스의 유입을 방지하게 하였다. 렌즈에서 발생하게 되는 비점수차제거와 정간거리 유지를 위해 S자형의 프레임으로 개발하였다. 결과: 완전한 시력교정과 가스차단이 가능하고 일반 안경처럼 안경렌즈를 교환하여 사용할 수 있게 되었으며 시선과 렌즈면의 경사로 발생하던 비점수차 0.53D~1.78D, 짧은 정간거리로 발생하던 0.07D~0.66D의 과교정, 전경각 미설정으로 발생하던 0.1D~0.3D의 비점수차를 제거할 수 있게 되었다. 결론: 방독면을 쓴 상태에서도 밝은 시야의 확보가 가능하여 전투력 향상과 인명구조 활동 등에서 큰 도움이 될 수 있을 것으로 예상된다.

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편심된 안경렌즈의 산각 위치에 따른 비점수차 계산: 편심에 의한 프리즘 처방 (The Astigmatism Calculation according to the Bevel Position of Decentered Spectacle Lens: Prism Prescription Lens by Eccentricity)

  • 김상현;서지근
    • 한국안광학회지
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    • 제11권2호
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    • pp.77-83
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    • 2006
  • 본 연구에서는 프리즘 처방을 위해 편심된 안경렌즈의 산각위치에 따른 수차와 경사각에 따른 수차를 계산하였다. 프리즘 처방을 위해서 일반적으로 일반 렌즈를 편심시켜 만든다. 광축과 주시축 사이의 차이는 수차를 발생시키기 때문에, 이런 경우 산각의 위치가 중요하다. 우리는 계산을 통하여 산각 회전 띠의 축이 (+)렌즈의 전면 곡률 중심을 지나는 것이 후면곡률 중심을 지나는 것보다 비점수차가 적게 발생하였고, 산각 회전 띠의 (-) 렌즈의 후면곡률 중심을 지나는 것이 전면보다 비점수차가 적게 발생한다는 결과를 얻었다. 렌즈의 굴절력이 클수록 비점수차가 작았다.

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