As extended reality (XR) technologies rapidly become as ubiquitous as today's mobile devices, supporting one-handed interaction becomes essential for XR. However, the prevalent Gaze + Pinch interaction model partially supports unimanual interaction, where users select, move, and rotate objects with one hand, but scaling typically requires both hands. In this work, we leverage the spatial alignment between gaze and hand as a mode switch to enable single-handed pinch-to-scale. We design and evaluate several techniques geared for one-handed scaling and assess their usability in a compound translate-scale task. Our findings show that all proposed methods effectively enable one-handed scaling, but each method offers distinct advantages and trade-offs. To this end, we derive design guidelines to support futuristic 3D interfaces with unimanual interaction. Our work helps make eye-hand 3D interaction in XR more mobile, flexible, and accessible.

翻译：随着扩展现实技术迅速普及，如同当今移动设备一般无处不在，支持单手交互成为扩展现实的关键需求。然而，当前主流的“视线+捏合”交互模式仅部分支持单手交互——用户可用一只手选择、移动和旋转物体，但缩放操作通常需要双手协同。本工作利用视线与手之间的空间对齐作为模式切换机制，实现了单手的捏合缩放操作。我们设计并评估了多种面向单手缩放的交互技术，并在复合平移-缩放任务中评估其可用性。实验结果表明，所有提出的方法均能有效支持单手缩放，但各方法具有不同的优势与权衡。基于此，我们推导出面向未来支持单手交互的三维界面设计指南。本研究有助于提升扩展现实中眼-手协同三维交互的移动性、灵活性与可及性。