The release of Microsoft's HoloLens headset addresses new types of issues that would have been difficult to design without such a hardware. This semi-transparent visor headset allows the user who wears it to view the projection of 3D virtual objects placed in its real environment. The user can also interact with these 3D objects, which can interact with each other. The framework of this new technology is called mixed reality. We had the opportunity to numerically transform a conventional human nutrition workshop for patients waiting for bariatric surgery by developing a software called HOLO_NUTRI using the HoloLens headset. Unlike our experience of user and conventional programmer specialized in the development of interactive 3D graphics applications, we realized that such a mixed reality experience required specific programming concepts quite different from those of conventional software or those of virtual reality applications, but above all required a thorough reflection about communication for users. In this article, we propose to explain our design of communication (graphic supports, tutorials of use of material, explanatory videos), a step which was crucial for the good progress of our project. The software was used by thirty patients from Le Puy-en-Velay Hospital during 10 sessions of one hour and a half during which patients had to take in hand the headset and software HOLO_NUTRI. We also proposed a series of questions to patients to have an assessment of both the adequacy and the importance of this communication approach for such experience. As the mixed reality technology is very recent but the number of applications based on it significantly increases, the reflection on the implementation of the elements of communication described in this article (videos, exercise of learning for the use of the headset, communication leaflet, etc.) can help developers of such applications.

翻译：微软HoloLens头戴设备的发布为新型应用场景的构建提供了可能，此前在没有此类硬件的情况下这些场景将难以设计。这款半透明遮光式头戴设备允许佩戴者在其真实环境中投射三维虚拟物体。用户还可与这些具备交互能力的虚拟物体进行互动。这项新技术的框架被称为混合现实。我们通过开发基于HoloLens头戴设备的HOLO_NUTRI软件，实现了对面向等待减肥手术患者的传统人类营养工作坊的数字化改造。与从事交互式三维图形应用开发的常规程序员和用户经验不同，我们意识到此类混合现实体验需要运用不同于传统软件或虚拟现实应用的特定编程概念，其核心更在于对用户通信机制的深度思考。本文拟阐述我们设计的通信方案（包括图形化支持、设备使用教程、解释性视频），该环节对项目顺利推进具有决定性意义。该软件在勒皮昂沃莱医院的10场90分钟培训中被30名患者使用，期间患者需自主操作头戴设备与HOLO_NUTRI软件。我们同时向患者提出系列问题，以评估该通信方案对此类体验的适配度与重要性。鉴于混合现实技术虽尚处萌芽期但相关应用数量激增，本文所述的通信要素实现方案（视频、设备操作练习教程、通信手册等）可为同类应用开发者提供参考。