Retinal Viewfinder - HCI International 2022 #HCII2022 (Oral presentation by Ippei Suzuki)

This slide was presented in Session "S033: Novel Input and Output Techniques - I" at the 24th International Conference on Human-Computer Interaction (HCII 2022).
https://2022.hci.international

【Publication】
Suzuki, I., Itoh, Y., Ochiai, Y. (2022). Retinal Viewfinder: Preliminary Study of Retinal Projection-Based Electric Viewfinder for Camera Devices. In: Kurosu, M. (eds) Human-Computer Interaction. Technological Innovation. HCII 2022. Lecture Notes in Computer Science, vol 13303. Springer, Cham. https://doi.org/10.1007/978-3-031-05409-9_12

【Project page】
https://digitalnature.slis.tsukuba.ac.jp/2022/06/retinal-viewfinder/

【Presenter】
Ippei Suzuki (鈴木 一平)
Ph.D. Student (Doctoral Program in Informatics)
Graduate School of Comprehensive Human Sciences
University of Tsukuba (JP)
Digital Nature Group (Yoichi Ochiai)
https://1heisuzuki.com

【Abstract】
This paper presents a prototype of a new type of electronic viewfinder (EVF) that uses a retinal projection system. A viewfinder that enables users to preview an image is one of the characteristics and important interfaces of a camera. However, people who require glasses or contact lenses face a problem when using a viewfinder as they cannot see the image easily. In the retinal projection system, a large depth of field projection will enable users to focus on the displayed image easily. To investigate the above hypothesis, we compared the existing EVF with the proposed method from the perspective of ease of focusing on subjects. The user study employed a person with bad eyesight who uses a visual aid. Experimental results indicate that in certain situations, the proposed method has an advantage in focusing when users look through the viewfinder without glasses or contact lenses.

Transcript

1. © Research and Development Center for Digital Nature Retinal Viewfinder: Preliminary Study of Retinal Projection-Based Electric Viewfinder for Camera Devices Ippei Suzuki, Yuta Itoh, Yoichi Ochiai Research and Development Center for Digital Nature, University of Tsukuba, Japan
2. 2 © Research and Development Center for Digital Nature Background Photography Process Adjust parameters Preview Take the photograph Main Steps of Photography
3. 3 © Research and Development Center for Digital Nature Background Preview Hardware Equipped on Camera Devices Image: https://www.sony.jp/ichigan/products/ILCE-7SM2/index.html Viewfinder Display Screen
4. 4 © Research and Development Center for Digital Nature Background Advantage of Viewfinders Advantages of Viewfinders cf. Display Screen Blocking surrounding light Stabilizing the camera by bracing it against their face & keeping their arm close to the body Concentration on taking photos by restricting the field of view
5. 5 © Research and Development Center for Digital Nature Background Commercially Available Viewfinders ɹImage (Left):https://dc.watch.impress.co.jp/docs/review/pentax100/1207316.html Image (Right): https://cweb.canon.jp/eos/lineup/rp/feature-reliability.html Optical Viewfinder OVF Ready-to-Use Viewfinders *SLR Electronic Viewfinder EVF Mirror Pentamirror Display
6. 6 © Research and Development Center for Digital Nature Background Di ff iculty of Viewfinder for People w/ Bad Eyesight Image (Left): https://news.mapcamera.com/maptimes/cameratechiquevol16/ Di ff iculty of Viewfinder for People w/ Bad Eyesight Limited range of diopter adjustment Colliding the glasses
7. 7 © Research and Development Center for Digital Nature Introduction Proposed System R-EVF Retinal Projection-Based Electric Viewfinder
8. 8 © Research and Development Center for Digital Nature Introduction Retinal Projection in the field of HMDs Image (Left): https://www.moguravr.com/retissa-display/ Image (Right): https://prtimes.jp/main/html/rd/p/000000001.000060779.html Retinal Projection e.g., RETISSA Display Providing a large depth of field projection enables one to focus on the displayed image easily
9. 9 © Research and Development Center for Digital Nature Introduction A R-EVF NR-EVF Normal Bad Eyesight* *Taken with an incorrect focus target to simulate the vision of a person with bad eyesight. 
 **This image is only for illustration purposes of bad eyesight. Image looks di ff erent from actual view due to the shooting environment.
10. 1 0 © Research and Development Center for Digital Nature Retinal Projection System Camera
11. 1 1 © Research and Development Center for Digital Nature Summary of Contribution 1. A method of building the R-EVF prototype 2. Investigations of the e ff ects of 
 using the prototype through a user study 3. Discussions of the results and 
 limitations of the current prototype.
12. 1 2 © Research and Development Center for Digital Nature Implementation
13. 1 3 © Research and Development Center for Digital Nature Implementation Proposed R-EVF Setup NR-EVF Setup
14. 1 4 © Research and Development Center for Digital Nature Image: https://www.amazon.co.jp/dp/B07KXLKZX4 Implementation Projector HD Pico Laser Projector HD301 Ultimates, Inc. Type of Display Micro-electro-mechanical systems (MEMS) mirror Resolution 1280 × 720 pixels Light source RGB Laser 
 with 20 lumen (±10%) light output Contrast Ratio 5000:1 Max video speed 60 Hz Same projectors are used for both R-EVF and NR-EVF
15. 1 5 © Research and Development Center for Digital Nature Implementation Yoichi Ochiai et al. 
 Make Your Own Retinal Projector: Retinal Near-eye Displays via Metamaterials. 
 SIGGRAPH 2018 Emerging Technologies R-EVF Optical Setup Reference
16. 1 6 © Research and Development Center for Digital Nature Implementation Retinal Projection-Based Electric Viewfinder R-EVF Setup Projector ND** *DCRA: Dihedral corner reflector array **ND: Filter for reducing intensity DCRA* Lens Mount w/o Lens Viewing Position
17. 1 7 © Research and Development Center for Digital Nature Implementation Non-retinal Projection-Based Electric Viewfinder Projector Screen Half-Mirror Lens Mount w/ Lens Viewing Position NR-EVF Setup
18. 1 8 © Research and Development Center for Digital Nature Implementation Projector ND DCRA Lens Mount w/o Lens Viewing Position Projector Screen Half-Mirror Lens Mount w/ Lens Viewing Position R-EVF Setup NR-EVF Setup
19. 1 9 © Research and Development Center for Digital Nature Implementation Projector ND DCRA Lens Mount w/o Lens Viewing Position Projector Screen Half-Mirror Lens Mount w/ Lens Viewing Position R-EVF Setup NR-EVF Setup
20. 2 0 © Research and Development Center for Digital Nature Implementation R-EVF Vision NR-EVF Vision
21. 2 1 © Research and Development Center for Digital Nature User Study
22. 2 2 © Research and Development Center for Digital Nature User Study Purpose To explore the e ff ectiveness of our method on focusing task when photography Participants 12 Participants | 19-30 years old All participants used a visual aid 4 participants first-time users of cameras w/manual focus
23. 2 3 © Research and Development Center for Digital Nature User Study Conditions Video Camera Camera EVFs Enclosure Target Object Monitor
24. 2 4 © Research and Development Center for Digital Nature User Study Conditions Target Subjects IEEE Reflection Target Drawing Mannequins Camera 30 0 Unit: cm 100 150 200
25. 2 5 © Research and Development Center for Digital Nature User Study Conditions EVFs Target Object Camera EVF
26. 2 6 © Research and Development Center for Digital Nature User Study Conditions Parameter Participants could change Focus Ring Face (Eye) Position Fixed: Camera Position, Exposure, Viewfinder Position, Lighting… Chin Rest (only for R-EVF)
27. 2 7 © Research and Development Center for Digital Nature User Study Conditions Visual Aid Viewfinder R-EVF NR-EVF w/ w/o R-EVF R-EVF NR-EVF NR-EVF
28. 2 8 © Research and Development Center for Digital Nature User Study Procedure Preparation 1. Quick eye test & Eye dominance test 
 2. Questionnaires e.g., daily photograph activity 3. Instruction on how to use EVFs *Used to view EVFs
29. 2 9 © Research and Development Center for Digital Nature User Study Procedure For Each Condition 1. The experimenter set the camera’s focus 
 to the minimum focusing distance 2. Participants were asked to focus 
 on each subject using a viewfinder 3. While keeping the focus setting 
 the experimenter pressed the shutter 
 which was set to a 2-second delay self-timer *1 photo was taken per condition per participant
30. 3 0 © Research and Development Center for Digital Nature User Study Procedure Post Focusing Task 1. Finally, participants were interviewed again 
 about how they experienced the experiment
31. 3 1 © Research and Development Center for Digital Nature User Study Result Focus Accuracy Data Processing Crop & Stabilized
32. 3 2 © Research and Development Center for Digital Nature User Study Result Focus Accuracy Data Processing Focus Measure = a higher value for a more focused image J.L. Pech-Pacheco et al. 
 Diatom autofocusing in brightfield microscopy: a comparative studyICPR-2000 46.57 Variance [ 0 1 0 1 −4 1 0 1 0 ] Source Convolved =Focus Measure 3x3 Laplacian kernel (Edge detection)
33. 3 3 © Research and Development Center for Digital Nature User Study Result Focus Accuracy Data Processing Focus Measure 46.57 37.61 = a higher value for a more focused image
34. 3 4 © Research and Development Center for Digital Nature User Study Result Focus Accuracy Data Processing Focus Measure 46.57 37.61 = a higher value for a more focused image
35. 3 5 © Research and Development Center for Digital Nature User Study Result Focus Accuracy Chart NR-EVF R-EVF NR-EVF R-EVF Naked Eye w/ Visual Aid 0 5 10 15 20 25 Focus Measure (higher is more in-focus) p > .05 No significant di ff erence
36. 3 6 © Research and Development Center for Digital Nature User Study Result Focus Accuracy White Drawing Mannequin NR-EVF R-EVF NR-EVF R-EVF Naked Eye w/ Visual Aid 25 30 35 40 45 50 Focus Measure (higher is more in-focus) p > .05 No significant di ff erence
37. 3 7 © Research and Development Center for Digital Nature User Study Result Focus Accuracy Blue Drawing Mannequin NR-EVF R-EVF NR-EVF R-EVF Naked Eye w/ Visual Aid Focus Measure (higher is more in-focus) p > .05 No significant di ff erence 25 30 35 40 45 50
38. 3 8 © Research and Development Center for Digital Nature User Study Result Focus Accuracy Red Drawing Mannequin NR-EVF R-EVF NR-EVF R-EVF Naked Eye w/ Visual Aid Focus Measure (higher is more in-focus) *p < .05 Significant di ff erence 25 30 35 40 45 50 * *
39. 3 9 © Research and Development Center for Digital Nature Discussion
40. 4 0 © Research and Development Center for Digital Nature Discussion Resolution Limitation caused 
 by DCRA & light source (Projector) Suppression of image degradation* Lattice *Yahagi et al. 2020. Suppression of floating image degradation 
 using a mechanical vibration of a dihedral corner reflector array. Combine with image processing 
 e.g., magnification or focus peaking? R-EVF has lower resolution than commercial available EVFs
41. 4 1 © Research and Development Center for Digital Nature Discussion Focusing Process In NR-EVF tasks without contact lenses, I could not see the image clearly. However, I judged whether in focus or not by repeating the focus adjustment.“ “ This becomes a problem when using autofocus as the manual focusing process is omitted in autofocus, and the user cannot judge whether the image is in focus during the focusing process.
42. 4 2 © Research and Development Center for Digital Nature Discussion Positioning Problem When using retinal projection, users are required 
 to place their eye tiny position Narrow field of view 
 when users see the image 
 from little bit distant e.g., with glasses Enlarging viewable area? Suitable camera shape for R-EVF?
43. 4 3 © Research and Development Center for Digital Nature Future Work What is optimal shape for a camera using the R-EVF? ?
44. © Research and Development Center for Digital Nature Retinal Viewfinder: Preliminary Study of Retinal Projection-Based Electric Viewfinder for Camera Devices Ippei Suzuki, Yuta Itoh, Yoichi Ochiai Research and Development Center for Digital Nature, University of Tsukuba, Japan