High resolution irradiance tailoring using multiple freeform surfaces

Abstract

More and more lighting applications require the design of dedicated optics to achieve a given radiant intensity or irradiance distribution. Freeform optics has the advantage of providing such a functionality with a compact design. It was previously demonstrated in [Bäuerle et al., Opt. Exp. 20, 14477-14485 (2012)] that the up-front computation of the light path through the optical system (ray mapping) provides a satisfactory approximation to the problem, and allows the design of multiple freeform surfaces in transmission or in reflection. This article presents one natural extension of this work by introducing an efficient optimization procedure based on the physics of the system. The procedure allows the design of multiple freeform surfaces and can render high resolution irradiance patterns, as demonstrated by several examples, in particular by a lens made of two freeform surfaces projecting a high resolution logo (530 × 160 pixels).

Light shaping for illumination

“…This section, by contrast, will demonstrate the power of algorithmically designed nonimaging optics with another example. Figure 7 shows the rendering of a lens together with the rather complicated irradiance pattern it generates (a logo) [33]. The resolution of the prescribed target distribution is 193 × 193 pixels, and the contrast is approximately 4:1.…”

Direct design of aspherical lenses for extended non-Lambertian sources in three-dimensional rotational geometry

“…Generally, the illumination design algorithms can be divided into two groups: zero-étendue algorithms [2][3][4][5][6][7][8][9] and algorithms for extended sources [10][11][12][13]. For a zero-étendue algorithm, the light source is assumed as an ideal source (a point source or a parallel beam), in which there is only one single ray passing through each point on the optical surface, as shown in Fig.…”

“…1(a). This simplistic assumption allows us to easily achieve a predefined deflection of the optical surface for each incident ray [6,9]. Since the étendue of an actual light source usually cannot be zero in practical applications, these zero-étendue algorithms are invalid in a compact design where the influence of the size or the angular extent of the extended source on the performance of an illumination system cannot be ignored.…”

Freeform lens collimating spectrum-folded Hadamard transform near-infrared spectrometer

“…Compared with traditional optical components, freeform optics can precisely control the distribution of light beams, and simplify the system with fewer surfaces, lower mass which reduces the difficulty in assembly [7][8][9][10]. In this study, we propose a novel source collimating approach by using freeform lens to extend the working wavelength range.…”