Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts.
Optom Vis Sci. 2021 Oct 1;98(10):1210-1226. doi: 10.1097/OPX.0000000000001790.
Photographic depiction helps to illustrate the primary and secondary field of view effects of low vision devices along with their utility to clinicians, patients, and caretakers. This technique may also be helpful for designers and researchers in improving the design and fitting of low vision devices.
The field of view through spectacles-mounted low vision devices has typically been evaluated using perimetry. However, the perimetric field diagram is different from the retinal image and often fails to represent the important aspects of the field of view and visual parameters. We developed a photographic depiction method to record and veridically show the field of view effects of these devices.
We used a 3D-printed holder to place spectacles-mounted devices at the same distance from the empirically determined reference point of the field of view in a camera lens (f = 16 mm) as they would be from an eye, when in use. The field of view effects of a bioptic telescope, a minifier (reverse telescope), and peripheral prisms were captured using a conventional camera, representing retinal images. The human eye pupil size (adjusting the F number: f/2.8 to f/8 and f/22 in the camera lens) and fitting parameters (pantoscopic tilt and back vertex distance) varied.
Real-world indoor and outdoor walking and driving scenarios were depicted as retinal images illustrating the field of view through low vision devices, distinguishing optical and obscuration scotomas, and demonstrating secondary effects (spatial distortions, viewpoint changes, diplopia, spurious reflection, and multiplexing effects) not illustrated by perimetric field diagrams.
Photographic depiction illustrates the primary and secondary field of view effects of the low vision devices. These images highlight the benefit and possible trade-offs of the low vision devices and may be beneficial in education and training.
照片描绘有助于说明低视力设备的主视野和次视野效果，以及它们对临床医生、患者和护理人员的实用性。这种技术对于设计师和研究人员改进低视力设备的设计和适配也可能有帮助。
通过视野计评估戴镜式低视力设备的视野。然而，视野图与视网膜图像不同，往往无法代表视野和视觉参数的重要方面。我们开发了一种摄影描述方法来记录和真实显示这些设备的视野效果。
我们使用 3D 打印支架将戴镜式设备放置在距相机镜头（f = 16mm）中视野的经验确定参考点相同的距离处，就像在使用时距眼睛的距离一样。使用常规相机捕获双目望远镜、减光镜（反向望远镜）和周边棱镜的视野效果，代表视网膜图像。人眼瞳孔大小（调整 F 数：相机镜头中的 f/2.8 到 f/8 和 f/22）和适配参数（镜架倾斜和后顶点距离）发生变化。
真实世界的室内和室外行走和驾驶场景被描绘为视网膜图像，说明通过低视力设备的视野，区分光学和遮挡性暗点，并展示次要影响（空间扭曲、视点变化、复视、虚假反射和复用效果），这些效果无法通过视野图表示。
摄影描述说明了低视力设备的主视野和次视野效果。这些图像突出了低视力设备的益处和可能的权衡，可能有助于教育和培训。
