Abstract

Spatial light modulator (SLM)-based tunable sources synthesize any specified spectral power distribution. However, their complexity makes a simpler version desirable. A prism before an SLM-projector is shown to synthesize spectra at least as effectively. Moreover, this simple setup projects two-dimensional (2-D) videos onto a one-dimensional (1-D) screen. Viewed through a prism (or grating), rainbow-colored renderings of grayscale videos emerge. The semitransparent, 2-D virtual images face each viewer all around the 1-D screen. Uncannily, mirrors around the 1-D screen cannot flip the images. In hindsight, SLM-based spectral synthesis is essentially a form of spectral encoding that is applicable to video projection, and beyond.

© 2014 Optical Society of America

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References

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2013 (2)

2012 (2)

S. Tominaga and T. Horiuchi, “Spectral imaging by synchronizing capture and illumination,” J. Opt. Soc. Am. A 29, 1764–1775 (2012).
[CrossRef]

J. P. Rice, S. W. Brown, D. W. Allen, H. W. Yoon, M. Litorja, and J. C. Hwang, “Hyperspectral image projector applications,” Proc. SPIE 8254, 82540R (2012).

2011 (1)

2009 (2)

A. Schwarz, A. Weiss, D. Fixler, Z. Zalevskya, V. Micó, and J. García, “One-dimensional wavelength multiplexed microscope without objective lens,” Opt. Commun. 282, 2780–2786 (2009).
[CrossRef]

M. Merman, A. Abramov, and D. Yelin, “Theoretical analysis of spectrally encoded endoscopy,” Opt. Express 17, 24045–24059 (2009).
[CrossRef]

2008 (2)

2007 (1)

2006 (3)

S. W. Brown, J. P. Rice, J. E. Neira, B. C. Johnson, and J. D. Jackson, “Spectrally tunable sources for advanced radiometric applications,” J. Res. Natl. Inst. Stand. Technol. 111, 401–410 (2006).
[CrossRef]

J. P. Rice, S. W. Brown, and B. C. Johnson, “Hyperspectral image projectors for radiometric applications,” Metrologia 43, S61 (2006).
[CrossRef]

A. Yilmaz, O. Javed, and M. Shah, “Object tracking: a survey,” ACM Comput. Surv. 38, 13 (2006).
[CrossRef]

2005 (2)

I. Fryc, S. W. Brown, G. P. Eppeldauer, and Y. Ohno, “LED-based spectrally tunable source for radiometric, photometric, and colorimetric applications,” Opt. Eng. 44, 111309 (2005).
[CrossRef]

N. MacKinnon, U. Stange, P. Lane, C. MacAulay, and M. Quatrevalet, “Spectrally programmable light engine for in vitro or in vivo molecular imaging and spectroscopy,” Appl. Opt. 44, 2033–2040 (2005).
[CrossRef]

2002 (1)

1997 (1)

1987 (1)

1983 (1)

Abramov, A.

Allen, D. W.

J. P. Rice, S. W. Brown, D. W. Allen, H. W. Yoon, M. Litorja, and J. C. Hwang, “Hyperspectral image projector applications,” Proc. SPIE 8254, 82540R (2012).

Brown, S. W.

J. P. Rice, S. W. Brown, D. W. Allen, H. W. Yoon, M. Litorja, and J. C. Hwang, “Hyperspectral image projector applications,” Proc. SPIE 8254, 82540R (2012).

J. P. Rice, S. W. Brown, and B. C. Johnson, “Hyperspectral image projectors for radiometric applications,” Metrologia 43, S61 (2006).
[CrossRef]

S. W. Brown, J. P. Rice, J. E. Neira, B. C. Johnson, and J. D. Jackson, “Spectrally tunable sources for advanced radiometric applications,” J. Res. Natl. Inst. Stand. Technol. 111, 401–410 (2006).
[CrossRef]

I. Fryc, S. W. Brown, G. P. Eppeldauer, and Y. Ohno, “LED-based spectrally tunable source for radiometric, photometric, and colorimetric applications,” Opt. Eng. 44, 111309 (2005).
[CrossRef]

Calatroni, J.

Case, S. K.

Eismann, M. T.

Eppeldauer, G. P.

I. Fryc, S. W. Brown, G. P. Eppeldauer, and Y. Ohno, “LED-based spectrally tunable source for radiometric, photometric, and colorimetric applications,” Opt. Eng. 44, 111309 (2005).
[CrossRef]

Farup, I.

Ferreira, C.

Fixler, D.

A. Schwarz, A. Weiss, D. Fixler, Z. Zalevskya, V. Micó, and J. García, “One-dimensional wavelength multiplexed microscope without objective lens,” Opt. Commun. 282, 2780–2786 (2009).
[CrossRef]

Froehly, C.

Fryc, I.

I. Fryc, S. W. Brown, G. P. Eppeldauer, and Y. Ohno, “LED-based spectrally tunable source for radiometric, photometric, and colorimetric applications,” Opt. Eng. 44, 111309 (2005).
[CrossRef]

Garcia, J.

García, J.

A. Schwarz, A. Weiss, D. Fixler, Z. Zalevskya, V. Micó, and J. García, “One-dimensional wavelength multiplexed microscope without objective lens,” Opt. Commun. 282, 2780–2786 (2009).
[CrossRef]

Garner, H. R.

H. R. Garner, “Variable spectrum generator,” U.S. patent6,657,758 B1 (2December2003).

Grusche, S.

F. Theilmann and S. Grusche, “An RGB approach to prismatic colours,” Phys. Educ. 48, 750 (2013).
[CrossRef]

Hong, J. H.

J. H. Hong, “Wavelength multiplexed two dimensional image transmission through single mode optical fiber,” U.S. patent5,315,423 A (24May1994).

Horiuchi, T.

S. Tominaga and T. Horiuchi, “Spectral imaging by synchronizing capture and illumination,” J. Opt. Soc. Am. A 29, 1764–1775 (2012).
[CrossRef]

T. Horiuchi, H. Kakinuma, and S. Tominaga, “Effective illumination control for an active spectral imaging system,” in Proceedings of the 12th International Symposium on Multispectral Color Science (Society for Imaging Science and Technology, 2010), pp. 529–534.

Hulsey, D. E.

Hwang, J. C.

J. P. Rice, S. W. Brown, D. W. Allen, H. W. Yoon, M. Litorja, and J. C. Hwang, “Hyperspectral image projector applications,” Proc. SPIE 8254, 82540R (2012).

Jackson, J. D.

S. W. Brown, J. P. Rice, J. E. Neira, B. C. Johnson, and J. D. Jackson, “Spectrally tunable sources for advanced radiometric applications,” J. Res. Natl. Inst. Stand. Technol. 111, 401–410 (2006).
[CrossRef]

Javed, O.

A. Yilmaz, O. Javed, and M. Shah, “Object tracking: a survey,” ACM Comput. Surv. 38, 13 (2006).
[CrossRef]

Johnson, B. C.

S. W. Brown, J. P. Rice, J. E. Neira, B. C. Johnson, and J. D. Jackson, “Spectrally tunable sources for advanced radiometric applications,” J. Res. Natl. Inst. Stand. Technol. 111, 401–410 (2006).
[CrossRef]

J. P. Rice, S. W. Brown, and B. C. Johnson, “Hyperspectral image projectors for radiometric applications,” Metrologia 43, S61 (2006).
[CrossRef]

Joshi, M.

U. Kanade and M. Joshi, “Programmable light source,” U.S. patent8,107,169 (31January2012).

Kakinuma, H.

T. Horiuchi, H. Kakinuma, and S. Tominaga, “Effective illumination control for an active spectral imaging system,” in Proceedings of the 12th International Symposium on Multispectral Color Science (Society for Imaging Science and Technology, 2010), pp. 529–534.

Kanade, U.

U. Kanade and M. Joshi, “Programmable light source,” U.S. patent8,107,169 (31January2012).

Kerekes, J.

Lane, P.

Leathers, R. A.

Lee, C.-C.

Lee, C.-K.

Lee, T.

Litorja, M.

J. P. Rice, S. W. Brown, D. W. Allen, H. W. Yoon, M. Litorja, and J. C. Hwang, “Hyperspectral image projector applications,” Proc. SPIE 8254, 82540R (2012).

Lo, M.-L.

Lohmann, A. W.

Lunazzi, J.

MacAulay, C.

MacKinnon, N.

Marom, E.

Mas, D.

Mendlovic, D.

Merman, M.

Meyn, J.-P.

J.-P. Meyn, “Colour mixing based on daylight,” Eur. J. Phys. 29, 1017–1031 (2008).
[CrossRef]

Micó, V.

A. Schwarz, A. Weiss, D. Fixler, Z. Zalevskya, V. Micó, and J. García, “One-dimensional wavelength multiplexed microscope without objective lens,” Opt. Commun. 282, 2780–2786 (2009).
[CrossRef]

Min, S.-W.

Müller, M.

M. Müller and L.-M. Schön, “Virtuelle Beugungsbilder am Gitter,” in Didaktik der Physik. Frühjahrstagung Münster, H. Groetzebach and V. Nordmeier, eds. (PhyDid B, 2011) pp. 1–9, http://phydid.physik.fu-berlin.de/index.php/phydid-b/article/view/288/348 .

Neira, J. E.

S. W. Brown, J. P. Rice, J. E. Neira, B. C. Johnson, and J. D. Jackson, “Spectrally tunable sources for advanced radiometric applications,” J. Res. Natl. Inst. Stand. Technol. 111, 401–410 (2006).
[CrossRef]

Nelson, N. R.

N. R. Nelson, “Hyperspectral scene generator and method of use,” U.S. patent7,106,435 B2 (12September2006).

Newton, I.

I. Newton, Opticks: Or, a Treatise of the Reflections, Refractions, Inflections and Colours of Light, 4th ed. (Dover Publications, 1979).

Ohno, Y.

I. Fryc, S. W. Brown, G. P. Eppeldauer, and Y. Ohno, “LED-based spectrally tunable source for radiometric, photometric, and colorimetric applications,” Opt. Eng. 44, 111309 (2005).
[CrossRef]

Quatrevalet, M.

Rice, J. P.

J. P. Rice, S. W. Brown, D. W. Allen, H. W. Yoon, M. Litorja, and J. C. Hwang, “Hyperspectral image projector applications,” Proc. SPIE 8254, 82540R (2012).

S. W. Brown, J. P. Rice, J. E. Neira, B. C. Johnson, and J. D. Jackson, “Spectrally tunable sources for advanced radiometric applications,” J. Res. Natl. Inst. Stand. Technol. 111, 401–410 (2006).
[CrossRef]

J. P. Rice, S. W. Brown, and B. C. Johnson, “Hyperspectral image projectors for radiometric applications,” Metrologia 43, S61 (2006).
[CrossRef]

Rivera, N.

Schaum, A. P.

Schön, L.-M.

M. Müller and L.-M. Schön, “Virtuelle Beugungsbilder am Gitter,” in Didaktik der Physik. Frühjahrstagung Münster, H. Groetzebach and V. Nordmeier, eds. (PhyDid B, 2011) pp. 1–9, http://phydid.physik.fu-berlin.de/index.php/phydid-b/article/view/288/348 .

Schwarz, A.

A. Schwarz, A. Weiss, D. Fixler, Z. Zalevskya, V. Micó, and J. García, “One-dimensional wavelength multiplexed microscope without objective lens,” Opt. Commun. 282, 2780–2786 (2009).
[CrossRef]

Seim, T.

Shah, M.

A. Yilmaz, O. Javed, and M. Shah, “Object tracking: a survey,” ACM Comput. Surv. 38, 13 (2006).
[CrossRef]

Søndrol, T.

Stange, U.

Sung, H.

Theilmann, F.

F. Theilmann and S. Grusche, “An RGB approach to prismatic colours,” Phys. Educ. 48, 750 (2013).
[CrossRef]

Tominaga, S.

S. Tominaga and T. Horiuchi, “Spectral imaging by synchronizing capture and illumination,” J. Opt. Soc. Am. A 29, 1764–1775 (2012).
[CrossRef]

T. Horiuchi, H. Kakinuma, and S. Tominaga, “Effective illumination control for an active spectral imaging system,” in Proceedings of the 12th International Symposium on Multispectral Color Science (Society for Imaging Science and Technology, 2010), pp. 529–534.

Weiss, A.

A. Schwarz, A. Weiss, D. Fixler, Z. Zalevskya, V. Micó, and J. García, “One-dimensional wavelength multiplexed microscope without objective lens,” Opt. Commun. 282, 2780–2786 (2009).
[CrossRef]

Wold, J. H.

Yang, T.-C.

Yang, T.-H.

Yelin, D.

Yilmaz, A.

A. Yilmaz, O. Javed, and M. Shah, “Object tracking: a survey,” ACM Comput. Surv. 38, 13 (2006).
[CrossRef]

Yoon, H. W.

J. P. Rice, S. W. Brown, D. W. Allen, H. W. Yoon, M. Litorja, and J. C. Hwang, “Hyperspectral image projector applications,” Proc. SPIE 8254, 82540R (2012).

Zalevsky, Z.

Zalevskya, Z.

A. Schwarz, A. Weiss, D. Fixler, Z. Zalevskya, V. Micó, and J. García, “One-dimensional wavelength multiplexed microscope without objective lens,” Opt. Commun. 282, 2780–2786 (2009).
[CrossRef]

ACM Comput. Surv. (1)

A. Yilmaz, O. Javed, and M. Shah, “Object tracking: a survey,” ACM Comput. Surv. 38, 13 (2006).
[CrossRef]

Appl. Opt. (8)

Eur. J. Phys. (1)

J.-P. Meyn, “Colour mixing based on daylight,” Eur. J. Phys. 29, 1017–1031 (2008).
[CrossRef]

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

J. Res. Natl. Inst. Stand. Technol. (1)

S. W. Brown, J. P. Rice, J. E. Neira, B. C. Johnson, and J. D. Jackson, “Spectrally tunable sources for advanced radiometric applications,” J. Res. Natl. Inst. Stand. Technol. 111, 401–410 (2006).
[CrossRef]

Metrologia (1)

J. P. Rice, S. W. Brown, and B. C. Johnson, “Hyperspectral image projectors for radiometric applications,” Metrologia 43, S61 (2006).
[CrossRef]

Opt. Commun. (1)

A. Schwarz, A. Weiss, D. Fixler, Z. Zalevskya, V. Micó, and J. García, “One-dimensional wavelength multiplexed microscope without objective lens,” Opt. Commun. 282, 2780–2786 (2009).
[CrossRef]

Opt. Eng. (1)

I. Fryc, S. W. Brown, G. P. Eppeldauer, and Y. Ohno, “LED-based spectrally tunable source for radiometric, photometric, and colorimetric applications,” Opt. Eng. 44, 111309 (2005).
[CrossRef]

Opt. Express (2)

Phys. Educ. (1)

F. Theilmann and S. Grusche, “An RGB approach to prismatic colours,” Phys. Educ. 48, 750 (2013).
[CrossRef]

Proc. SPIE (1)

J. P. Rice, S. W. Brown, D. W. Allen, H. W. Yoon, M. Litorja, and J. C. Hwang, “Hyperspectral image projector applications,” Proc. SPIE 8254, 82540R (2012).

Other (9)

U. Kanade and M. Joshi, “Programmable light source,” U.S. patent8,107,169 (31January2012).

H. R. Garner, “Variable spectrum generator,” U.S. patent6,657,758 B1 (2December2003).

M. Müller and L.-M. Schön, “Virtuelle Beugungsbilder am Gitter,” in Didaktik der Physik. Frühjahrstagung Münster, H. Groetzebach and V. Nordmeier, eds. (PhyDid B, 2011) pp. 1–9, http://phydid.physik.fu-berlin.de/index.php/phydid-b/article/view/288/348 .

I. Newton, Opticks: Or, a Treatise of the Reflections, Refractions, Inflections and Colours of Light, 4th ed. (Dover Publications, 1979).

N. R. Nelson, “Hyperspectral scene generator and method of use,” U.S. patent7,106,435 B2 (12September2006).

T. Horiuchi, H. Kakinuma, and S. Tominaga, “Effective illumination control for an active spectral imaging system,” in Proceedings of the 12th International Symposium on Multispectral Color Science (Society for Imaging Science and Technology, 2010), pp. 529–534.

J. H. Hong, “Wavelength multiplexed two dimensional image transmission through single mode optical fiber,” U.S. patent5,315,423 A (24May1994).

W. Rueckner, “The Spectrum,” http://sciencedemonstrations.fas.harvard.edu/icb/icb.do?keyword=k16940&pageid=icb.page93265 .

J. W. v. Goethe, Farbenlehre (Cotta, 1810). http://www.farben-welten.de/farben-welten/goethes-farbenlehre/enthuellung-der-theorie-newtons/erste-proposition-erstes-theorem-2.html .

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Figures (20)

Fig. 1.
Fig. 1.

SNS spectral synthesis. Multiple white lines [as shown on the personal computer (PC) monitor] are projected through a dispersive element for synthesis DES, creating multiple Newtonian spectra on screen S1. Each of them supplies a different color stripe (here: red, violet, yellow, green, cyan, and blue) to a slit at the linear locus of spectral synthesis LS.

Fig. 2.
Fig. 2.

Setup geometry for SNS (top view). Our setup has dP=0.07m; dS=1.93m. The light at LS is let through a slit of width w=1±0.1mm and analyzed on screen S2 with a grating G (groove density g=1000/mm). Using coordinates x to describe the undispersed grayscale pattern, we introduce xS for the dispersed grayscale pattern.

Fig. 3.
Fig. 3.

Deriving spectral bandwidth from dispersion diagrams. 100% spectral intensity is symbolized by white areas, 0% by gray areas. (a) Wavelength distribution of alternating white and black pixels, projected onto screen S1, undispersed. (b) Wavelength distribution of the dispersed pixels (irrelevant parts at lower contrast). We obtained (b) by shearing the wavelength distribution from (a) according to dispersion vector s. Bandwidth ΔλLS(x) depends on pixel width Δx (on S1) and slit width w.

Fig. 4.
Fig. 4.

Photos of SNS spectral synthesis. (a) Projected grayscale patterns on S1. The slit defines LS. (b) The same patterns, dispersed by DES across S1. The Newtonian spectra of AB and CD kiss each other at LS. (c) The slit spectra on S2 are a rainbow-colored version of the grayscale patterns.

Fig. 5.
Fig. 5.

Spectral lines from every other white pixel column. The heavy, black curve shows the output SPD from pattern 1 in Fig. 4(a).

Fig. 6.
Fig. 6.

Illuminant E (dashed). Whereas pattern 2 from Fig. 4(a) yields an irregular SPD (dotted), pattern 3 creates a uniform SPD (solid).

Fig. 7.
Fig. 7.

Magenta. The specified optimum color (dashed) is approximately synthesized (solid) using pattern 4 from Fig. 4(a).

Fig. 8.
Fig. 8.

Gaussian SPD at 570 nm, FWHM=50nm. The specified Gaussian (dashed) is approximately synthesized (solid) with pattern 5 from Fig. 4(a).

Fig. 9.
Fig. 9.

Gaussian SPD at 490 nm, FWHM=5nm. The specified Gaussian (dashed) is closely matched (solid) using pattern 6 from Fig. 4(a).

Fig. 10.
Fig. 10.

Imaging principle of PICS. The dispersion diagram shows the wavelength distribution of a white ‘F’ projected through DES. As any grayscale image, it consists of congruent, monochromatic images. These are dispersed by DES along the xS-axis, each contributing a different image stripe to the λ-y-plane (at a given coordinate xS). A dispersive element for analysis DEA translates the λ-y-plane into two spatial dimensions, thus arranging the image stripes as a rainbow-colored version of the grayscale image.

Fig. 11.
Fig. 11.

Use of the SNS tunable source for PICS (top view). A capellini at LS serves as a 1-D translucent projection screen. It is viewed through DEA, for which we use a direct-vision prism, or a grating (g=1000/mm).

Fig. 12.
Fig. 12.

PICS examples. (a) Original grayscale image of Lena. (b) Spectral image of a capellini. (c) High-resolution spectral image of a capellini.

Fig. 13.
Fig. 13.

Different spectral image proportions for different DEA.

Fig. 14.
Fig. 14.

Mirror-immunity with PICS. (a) A regular 2-D image in front of an upright mirror M is flipped in the mirror; it is not mirror-immune. (b) An upright 1-D screen has an identically oriented mirror image; it is mirror-immune. (c) Hence, even its spectral image (here featuring Lena) is mirror-immune.

Fig. 15.
Fig. 15.

Multiple-screen, multiple-image PICS. (a) Arrangement of four grayscale portraits (Newton, Fresnel, Goethe, and Huygens) in a presentation slide. (b) The slide was projected across four capellini through a single direct-vision prism as DES. Photos (c) and (d) were directly taken through a transmission grating as DEA at positions 1 and 2. Like rotatable banners attached to the capellini, the spectral portraits always face the viewer. The direct-vision prism at the projector [in photo (d) a white spot] can be flipped horizontally to flip each portrait horizontally.

Fig. 16.
Fig. 16.

Image resolution on a 1-D screen, approximated with a 2-D screen. (a) A grayscale image of Lena (looking left) is projected through DES so that its constituent monochromatic images are mutually displaced. These yield a blurry image. The 2-D projection screen is successively narrowed (from w1=17cm; w2=8cm; w3=2cm to w4=0.5cm). (b) A parallel DEA mutually displaces the monochromatic images on the screen even more. Thus, the image gets even blurrier, with Lena still looking left. At w=w4, Lena turns to the right, the image becoming relatively sharp (cf. Section 3.C.3). (c) An antiparallel DEA compensates the displacement among the monochromatic images. These compose a sharp image of Lena looking left.

Fig. 17.
Fig. 17.

The virtual image inspected through DEA (top view) is geometrically analogous to a real image projected through it. (Tracing the dispersed rays to an effective plane of refraction inside the prism simplifies the construction, cf. Fig. 2).

Fig. 18.
Fig. 18.

Analogy for the asymmetry in PICS image resolution: arranging image stripes in reverse order creates a reversed, but blurrier image.

Fig. 19.
Fig. 19.

Deriving PICS spectral image resolution from dispersion diagrams. In (a) and (d), the wavelength distribution of a grayscale image, dispersed by DES according to dispersion vector s, contains a spectral stack of width w at the linear locus (accentuated) that represents all grayscale pixels as spectral pixels. In (b), (c), and (e), additional dispersion by DEA shears the spectral stack according to dispersion vector a. Thus, the spread-out spectral pixels form a spectral image. Its image resolution depends on the relative dispersive displacement for analysis, a/s. (a) At a/s=0, all spectral pixels are superposed. (b) At a/s=1, all spectral pixels lie next to each other. (c) At a/s=+1, spectral pixels partially overlap. In (d), where a/s=0, and in (e), where a/s=0.5, the dispersion of DES is twice as strong as in (a)–(c). This allows more pixels to be represented at the linear locus, yielding higher pixel resolution compared to (b). (f) The spectral pixel width ΔxA, and the FWHM of a spectral pixel, ΔxH, depend on the width w of the line of light at the linear locus, on the grayscale pixel width Δx, and the relative dispersive displacement for analysis, a/s.

Fig. 20.
Fig. 20.

PICS spectral image resolution in terms of grayscale image resolution, calculated with Eqs. (15)–(17), cf. Eqs. (2) and (8). (a) Image resolution is decreased by decreasing the absolute value |a| of the dispersive displacement for analysis, at fixed dispersive displacement for synthesis s. Here, s=150Δx. (b) Image resolution is improved by increasing the absolute value |s| of the dispersive displacement for synthesis, at fixed dispersive displacement for analysis a. Here, a=150Δx, and RS refers to the grayscale image resolution at |s|=150Δx.

Equations (20)

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AC¯=BD¯=wSΔx.
s=2tan(0.5δS)dS.
wS=|s|+Δx,
s=sx^S,
ΔλLS(x,w)=|λLS(xΔx2)λLS(x+Δx2)|(1+wΔx).
λLS(x)λRλRλB|s||x|.
ΔλLS(x,w)|λRλBN1|(1+wΔx),
a=2tan(0.5δA)dA.
wA=|a|+w,
a=ax^A,
hA=hS.
wAhA=[|tan(0.5δA)dA|+0.5w|tan(0.5δS)dS|+0.5Δx]wShS.
ΔxA=|aN1|+|a+sN1|(wΔx).
ΔxA=|as|Δx+|as+1|w.
ΔxH=|as|Δx,foras0.5,
ΔxH=ΔxA|as|w,foras0.5.
RA=wAΔxH.
ΔxA=|aN1|+|a+sAN1|(wΔx).
ΔxH=|as|Δx,forasA0.5,
ΔxH=(Δxw)|as|+w|a+sAs|,forasA0.5.

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