Abstract

Refractive eyepiece design forms are often limited by chromatic aberrations and require a mix of glass types to achieve sufficient correction, thus they are not conducive to manufacture in volume. Reflective surfaces are inherently achromatic and can be produced in volume, but rotationally symmetric reflective surfaces are either used with lossy obscurations or are incapable of correcting rotationally variant aberrations when used in an unobscured form. Freeform optics enable unobscured reflective design forms with excellent image quality. Here, we document the design, fabrication, and assembly of an all-reflective high-end electronic viewfinder that shows the applicability of freeform surfaces to eyepiece design forms.

© 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

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References

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  1. W. J. Smith, Modern Lens Design, 2nd ed. (Mcgraw-hill, 2004).
  2. K. P. Thompson, “Description of the third-order optical aberrations of near-circular pupil optical systems without symmetry,” J. Opt. Soc. Am. A 22(7), 1389–1401 (2005).
    [Crossref]
  3. J. M. Sasián, “How to approach the design of a bilateral symmetric optical system,” Opt. Eng. 33(6), 2045–2061 (1994).
    [Crossref]
  4. K. Fuerschbach, J. P. Rolland, and K. P. Thompson, “Theory of aberration fields for general optical systems with freeform surfaces,” Opt. Express 22(22), 26585–26606 (2014).
    [Crossref]
  5. A. Bauer and J. P. Rolland, “Design of a freeform electronic viewfinder coupled to aberration fields of freeform optics,” Opt. Express 23(22), 28141–28153 (2015).
    [Crossref]
  6. A. Bauer, E. M. Schiesser, and J. P. Rolland, “Starting geometry creation and design method for freeform optics,” Nat. Commun. 9(1), 1756 (2018).
    [Crossref]
  7. L. G. Cook, “Three mirror anastigmatic optical system,” US Pat. No. 4,265,510 (1981).
  8. S. Kim, S. Chang, S. Pak, K. J. Lee, B. Jeong, G-j. Lee, G. H. Kim, S. K. Shin, and S. M. Yoo, “Fabrication of electroless nickel plated aluminum freeform mirror for an infrared off-axis telescope,” Appl. Opt. 54(34), 10137–10144 (2015).
    [Crossref]
  9. K. Fuerschbach, K. P. Thompson, and J. P. Rolland, “Interferometric measurement of a concave, phi-polynomial, Zernike mirror,” Opt. Lett. 39(1), 18–21 (2014).
    [Crossref]
  10. K. Fuerschbach, G. E. Davis, K. P. Thompson, and J. P. Rolland, “Assembly of a freeform off-axis optical system employing three phi-polynomial Zernike mirrors,” Opt. Lett. 39(10), 2896–2899 (2014).
    [Crossref]

2018 (1)

A. Bauer, E. M. Schiesser, and J. P. Rolland, “Starting geometry creation and design method for freeform optics,” Nat. Commun. 9(1), 1756 (2018).
[Crossref]

2015 (2)

2014 (3)

2005 (1)

1994 (1)

J. M. Sasián, “How to approach the design of a bilateral symmetric optical system,” Opt. Eng. 33(6), 2045–2061 (1994).
[Crossref]

Bauer, A.

A. Bauer, E. M. Schiesser, and J. P. Rolland, “Starting geometry creation and design method for freeform optics,” Nat. Commun. 9(1), 1756 (2018).
[Crossref]

A. Bauer and J. P. Rolland, “Design of a freeform electronic viewfinder coupled to aberration fields of freeform optics,” Opt. Express 23(22), 28141–28153 (2015).
[Crossref]

Chang, S.

Cook, L. G.

L. G. Cook, “Three mirror anastigmatic optical system,” US Pat. No. 4,265,510 (1981).

Davis, G. E.

Fuerschbach, K.

Jeong, B.

Kim, G. H.

Kim, S.

Lee, G-j.

Lee, K. J.

Pak, S.

Rolland, J. P.

Sasián, J. M.

J. M. Sasián, “How to approach the design of a bilateral symmetric optical system,” Opt. Eng. 33(6), 2045–2061 (1994).
[Crossref]

Schiesser, E. M.

A. Bauer, E. M. Schiesser, and J. P. Rolland, “Starting geometry creation and design method for freeform optics,” Nat. Commun. 9(1), 1756 (2018).
[Crossref]

Shin, S. K.

Smith, W. J.

W. J. Smith, Modern Lens Design, 2nd ed. (Mcgraw-hill, 2004).

Thompson, K. P.

Yoo, S. M.

Appl. Opt. (1)

J. Opt. Soc. Am. A (1)

Nat. Commun. (1)

A. Bauer, E. M. Schiesser, and J. P. Rolland, “Starting geometry creation and design method for freeform optics,” Nat. Commun. 9(1), 1756 (2018).
[Crossref]

Opt. Eng. (1)

J. M. Sasián, “How to approach the design of a bilateral symmetric optical system,” Opt. Eng. 33(6), 2045–2061 (1994).
[Crossref]

Opt. Express (2)

Opt. Lett. (2)

Other (2)

L. G. Cook, “Three mirror anastigmatic optical system,” US Pat. No. 4,265,510 (1981).

W. J. Smith, Modern Lens Design, 2nd ed. (Mcgraw-hill, 2004).

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Figures (8)

Fig. 1.
Fig. 1. Optical layout of the final 5-mirror viewfinder design.
Fig. 2.
Fig. 2. MTF plots for the final nominal design evaluated over the worst 4 mm subpupil within the full 12 mm eyebox and shown for the + 5, −5, and 0 diopter focus positions. The vertical blue bars indicate the MTF goals for the nominal design.
Fig. 3.
Fig. 3. (left) The paths from the OLED to the eyebox are shown, where the royal blue rays take the intended path and all other colored rays take a different path and are, therefore, considered stray light. (right) With the addition of 3 baffles to the design, all of the stray light can be blocked without vignetting the FOV. The mirrors were modeled as 100% reflective and all other surfaces were modeled as 100% absorptive.
Fig. 4.
Fig. 4. Examples of the residual surface roughness on a freeform mirror due to the diamond machining.
Fig. 5.
Fig. 5. Stainless steel monoblock housing cut using electrical discharge machining.
Fig. 6.
Fig. 6. Viewfinder assembly with housing, linear stage for display positioning, and eyecup.
Fig. 7.
Fig. 7. The HD (1920 × 1080 pix) test pattern to be projected through the viewfinder. The center sub-pattern is shown zoomed-in as an inset. Each grid consists of single rows/columns of sub-pixels for each color. Each sub-pattern measures 730 µm on each side on the microdisplay.
Fig. 8.
Fig. 8. Images of the test pattern displayed on the microdisplay captured by a camera sensor located at the real image produced by the + 5 diopter configuration of the viewfinder using a 4 mm pupil. The image at the center corresponds to the center of the FOV and the images in the corners correspond to the respective corner of the FOV. Each magnified sub-pattern measures 16.25 mm on each side.

Tables (3)

Tables Icon

Table 1. Design specifications.

Tables Icon

Table 2. Assembly and figure tolerances. Units of waves are measured at λ = 587 nm.

Tables Icon

Table 3. MTF results of Monte Carlo analysis using the tolerances listed in Table 1 evaluated over the worst performing subpupil for the 0° and 90° azimuths at 40 cyc/mm.

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