Mobile Projectors Using Scanned Beam Displays

Sprague, R.; Champion, M.; Brown, Malcolm; Brown, Dean; Freeman, Mark O.; Niesten, Maarten

doi:10.1002/9780470994641.ch21

Cited by 13 publications

(6 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this assumption, we demonstrated that the autocorrelation function of the illuminated laser beam can be represented as a product of two factors [Eq. (21)]. Independence of the sum in Eq.…”

Section: Simulation Of the Optical System With An Arbitrary Numericalmentioning

confidence: 99%

“…The value of the numerical aperture of the objective lens is the parameter that determines the effect of speckle suppression in this method [3,17]. The method can be used in 1D laser projectors [18][19][20] and in laserpointer projectors [21,22]. However, because a laser-pointer projector cannot use a large mirror due to the requirement of very rapid mirror vibration, the method is effective only for 1D scanning-laser projectors.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Full speckle suppression in laser projectors using two Barker code-type diffractive optical elements

et al. 2012

View full text Add to dashboard Cite

The mathematical model of a speckle-suppression method based on two Barker code-type diffractive optical elements (DOEs) moving in orthogonal directions is developed. The analytic formulae for speckle suppression efficiency are obtained. The model indicates that the one pair of DOEs can be used for laser beams of different colors. The speckle contrast is not dependent on the distance from the viewer to the screen until the distance decreases below the distance where the spatial resolution of the eye on the screen is less than the length of the image of the DOE structure period on the screen. The analysis of the simulated results demonstrates that the method can decrease the speckle contrast to less than 5%, which is below human eye sensitivity, with an optical efficiency greater than 90%.

show abstract

Section: Simulation Of the Optical System With An Arbitrary Numericalmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Full speckle suppression in laser projectors using two Barker code-type diffractive optical elements

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Therefore, laser illumination is the optimal solution for mobile devices such as laser projectors [1][2][3][4][5][6][7]. However, speckle noise [6,7] severely deteriorates the image quality obtained under coherent illumination.…”

Section: Introductionmentioning

confidence: 99%

Optical schemes for speckle suppression by Barker code diffractive optical elements

et al. 2013

View full text Add to dashboard Cite

A method for speckle suppression based on Barker code and M-sequence code diffractive optical elements (DOEs) is analyzed. An analytical formula for the dependence of speckle contrast on the wavelength of the laser illumination is derived. It is shown that speckle contrast has a wide maximum around the optimal wavelength that makes it possible to obtain large speckle suppression by using only one DOE for red, green, and blue laser illumination. Optical schemes for implementing this method are analyzed. It is shown that the method can use a simple liquid-crystal panel for phase rotation instead of a moving DOE; however, this approach requires a high frequency of liquid-crystal switching. A simple optical scheme is proposed using a 1D Barker code DOE and a simple 1D liquid-crystal panel, which does not require a high frequency of liquid-crystal switching or high-accuracy DOE movement.

show abstract

“…Therefore, it is the optimal solution for many optical devices [1][2][3][4][5][6]. However, the quality of images created using coherent laser illumination severely deteriorates because of granular modulation caused by speckle phenomena [7,8].…”

Section: Introductionmentioning

confidence: 99%

Experimental evaluation of speckle suppression efficiency using a moving 2D Barker code DOE

et al. 2013

View full text Add to dashboard Cite

This paper reports the findings from an experimental evaluation of speckle suppression efficiency using a method based on a moving 2D Barker code diffractive optical element (DOE). The optical setup and the optical scheme parameters of the method are presented. A speckle contrast of ~4.4-5.3% and speckle suppression coefficient (coefficient of speckle contrast reduction) of k>8 was obtained in experiments. However, the experimentally obtained speckle suppression coefficient was approximately 1.5 times smaller than the theoretical prediction. It is speculated that the discrepancy between the theoretical and the experimental data is due to an inexact match between the optical setup and the optimal optical parameters of the method. Analysis of the experimental data revealed that once the optical scheme is optimized, it will be possible to obtain a speckle suppression that is closer to the theoretical prediction.

show abstract

Mobile Projectors Using Scanned Beam Displays

Cited by 13 publications

References 0 publications

Full speckle suppression in laser projectors using two Barker code-type diffractive optical elements

Full speckle suppression in laser projectors using two Barker code-type diffractive optical elements

Optical schemes for speckle suppression by Barker code diffractive optical elements

Experimental evaluation of speckle suppression efficiency using a moving 2D Barker code DOE

Contact Info

Product

Resources

About