Chiral spin constrained assemblies for polarized optical mapping

Abstract

Optical-enabled identification and interaction provide an integral link between the digital and physical realms. However, nowadays optic-encodings, predominantly reliant on light’s intensity and wavelength, are hindered by environmental light interference and limited information capacity. The introduction of unusual polarization states, such as circular polarization—which is absent from ordinary surroundings—holds promise for higher-dimensional interaction. Here, we propose a circularly polarized optical mapper capable of generating high-entropy, noise-resistant keys, serving as a physical interface for unique interaction process between parties. To materialize this mapper, we developed an automated, in situ synthesis platform that facilitates the self-acting fabrication of robust, solid-state, chiral optical spin constrained assemblies. Our mappers, formed by randomized arrays of discrete assemblies, demonstrate near-theoretical performance in uniformity (0.4917), uniqueness (0.4968), and reliability (0.9355). By emitting high-dimensional spin-polarized light, our mappers enable both far-field readout and near-field authentication, with resistance to stray light interference, offering promising applications in the internet of things, augmented reality, and beyond.

Chiral optical spin constrained assemblies enable high-dimensional polarized optical mapping for cascade object recognition.

INTRODUCTION

Optical information used in recognition technologies offers high accuracy and rapid processing speeds, facilitating precise object identification and tracking across diverse applications (1–4). The integration of robust hardware devices, particularly in enclosed environments, is essential, as these devices provide reliable reference points independent of external conditions, thereby ensuring efficient interactions between the digital and physical realms (5–7).

Optical mapping, typically using the controllability and multidimensional modulation of fluorescent signals (e.g., wavelength, intensity, and lifetime), establishes a unique link between physical objects and their digital counterparts through nondeterministic manufacturing processes (8–10). While effective for object identification and verification, conventional methods are highly influenced by ambient light interference, reducing efficiency in visually complex environments (11–13). Incorporating higher-dimensional characteristics of light, that is, polarization, into optical mapping—referred to as polarized optical mappers—shows promising advantages (14–17). Among all types of polarized light, circularly polarized one exhibits enhanced resistance to environmental light interference (e.g., scattered or stray light), allowing for better signal-to-noise ratio by effectively removing background noise (18–20). In addition, circularly polarized light enables more complex response patterns, enhancing the uniqueness and robustness of the mapping (21).

Solid-state and stable chiral optical spin materials (22–26)—referring to the structures that are robust, not easily destructible or disturbed, and capable of emitting highly asymmetric circularly polarized light—are considered ideal candidates for polarized optical mappers. While integrating macroscopic helical structures [such as chiral liquid crystals (CLCs)] with various luminescent components can achieve high-performance chiral optical spin materials (offering luminescence dissymmetry factor, g_lum > 10⁻¹) (27, 28), their fluidity at working temperatures and sensitivity to external perturbations limit their use (29, 30). CLC polymers offer better stability but suffer from poor processability, and current synthesis methods are labor intensive and nonscalable (31–33). To overcome these limitations, introducing reactive liquid crystal monomers into CLCs, followed by shearing into microdroplets and in situ photopolymerization, promises to enable the formation of solid, durable, constrained assemblies with both stability and processability.

Here, we report the universal fabrication of a series of chiral optical spin constrained assemblies (OSCAs) through an automated, in situ synthesis and monitoring system, using a designed solidified-in-place helical assembly strategy. These OSCA materials, incorporating alternative luminescent components including organic dyes, organic-inorganic complexes, and quantum dots, form the foundation of polarized optical mappers. As-achieved mappers enable robust identification by filtering out background noise in far-field readings and ensuring unique authentication through near-field responses. This polarized optical mapping establishes a highly secure and reliable physical-to-digital connection, greatly enhancing the potential for intelligent information interaction.

RESULTS

Polarized optical mappers enabled by OSCA

In our concept, we introduce a technological platform that uses micromaterials with highly asymmetric emission to construct discrete arrays as optical media—termed polarized optical mappers. These mappers use the circular polarization character induced by photonic media to deliver unique and robust optical encodings. To realize this cryptographic primitive—that is, polarized optical mapping—robust, durable, and processable materials with strong circularly polarized emission are essential. Thus, OSCA materials are configurated using a developed solidified-in-place helical assembly strategy to construct for this purpose. A small number of chiral dopants (R/S5011) with high helical twisting power induce chiral ordering in liquid crystals to ensure their polarized optical performance. By incorporating reactive mesogens (RM257), the helical configuration can be preserved via ultraviolet-induced polymerization (Fig. 1, A and B). Last, the resulting OSCA materials are subsequently dispersed into a polymer matrix to construct final polarized optical mappers (Fig. 1C).

Fig. 1. Synthesis of OSCA materials with highly asymmetric emission and their application in polarized optical mapping.

(A) Molecular formula for constructing OSCA materials, including liquid crystal monomers, reactive monomers, chiral dopants for inducing helical alignment, high-quality luminescent guests, and photoinitiators for ultraviolet polymerization. (B) Schematic diagram of the helical structure within chiral OSCA materials and their tunable left-handed (LH) and right-handed (RH) circularly polarized emissions. (C) Polarized optical mapper fabrication. The components are initially preassembled to form helical superstructures, which are then shear assembled into microdroplets via microfluidic and in situ polymerized to form durable OSCA microspheres. These materials are randomly dispersed into a polymer matrix to construct the polarized optical mappers. The right panel showed the x-ray three-dimensional reconstruction of the mapper. Scale bar, 500 μm. (D) Concept of polarized optical mapping, illustrating the linking between physical objects and their corresponding optical responses, thereby generating unique encodings for the formers. (E) Principle of image acquisition and encoding. LH and RH circularly polarized images are initially captured through a designed optical setup; then, the acquired images are processed to obtain unique encoding.

Mathematically, polarized optical mapping can be modeled as a parametric function that maps a domain (physical object properties, such as surface topology or material structure) into an expanded codomain of optical responses (Fig. 1D), that is

$$\begin{array}{c}f:P\to D,P=\left(p_{1,}{p}_{2,\dots ,}{p}_n\right),D=\left(d_{1,}{d}_{2,\dots ,}{d}_m\right)\hfill \end{array}$$

where the function f represents the mapping relationship, the variable P denotes the specific attributes of physical objects, and D signifies their unique digital identities. Specifically, this translates physical object characteristics into unique, quantifiable optical markers, generating distinct polarized optical signals for identification and complex signal encodings (Fig. 1E).

To validate this design, we invented an automated in situ synthesis and monitoring system integrating injection, control, and monitoring modules. The injection module enables precise and continuous fluid delivery; the monitoring module allows real-time visualizing of material formation; and the control module dynamically adjusts flow parameters based on feedback, ensuring accurate and continuous synthesis of OSCA materials (Fig. 2A and figs. S1 and S2). Specifically, liquid crystals, chiral dopants, and luminescent guests were first coassembled into a preassembled helical superstructure. These preassemblies were subsequently introduced into a microfluidic chip via the injection module as the dispersed phase, with a 5 wt % polyvinyl alcohol (PVA) aqueous solution acting as the surfactant and continuous phase (movie S1). Leveraging integrated microfluidic device, the preassemblies underwent shearing by the continuous phase to form microdroplets, followed by in situ assembly and polymerization (figs. S3 and S4). This platform enabled the synthesis of OSCA materials incorporating various luminescent guests, including organic dyes (figs. S5 and S6), lanthanide complexes (fig. S7), and quantum dots (fig. S8), thereby demonstrating the versatility and universality of synthesis (Fig. 2, B and C).

Fig. 2. Synthesis and molecular alignment of OSCA materials.

(A) Schematic diagram of the in situ automated synthesis and monitoring platform for OSCA material synthesis: It consists of control, injection, and monitoring modules. The injection module includes two injection pumps for the dispersion phase and continuous phase, as well as a microfluidic device; the monitoring module is a designed microscope composed of an eyepiece, an objective, and a camera; the control module uses a computer connected to the injection pumps and the microscope. UV, ultraviolet. (B) Photoluminescence (PL) spectra of the OSCA materials based on multicolor fluorescent dyes, InP/ZnSeS/ZnS quantum dots, and Eu complex luminescent guests, respectively. a.u., arbitrary units. (C) Photograph of the mixed OSCA materials under ultraviolet excitation. Scale bar, 1 cm. (D) Evolution of the molecular orientation in OSCA materials over time under the influence of PVA. Top row illustrates the molecular transition from a completely disordered state upon initial synthesis to the fully ordered equilibrium state, and corresponding POM images are shown in bottom. Scale bar, 50 μm. (E) POM images of the fully oriented OSCA materials observed under reflection (left column) and transmission (right column) modes, respectively. Scale bar, 50 μm. (F to H) XRD patterns (F) and two-dimensional GIWAXS patterns [(G) and (H)] of CLC prepolymer assemblies and the OSCA materials after polymerization.

The PVA solution can promote surface anchoring and alignment of the CLC components, allowing the helical orientation in the synthesized OSCA materials to reach equilibrium over time (Fig. 2D and fig. S9). Photopolymerization preserved the molecular arrangement established during the monomer stage, transforming the materials into durable, solid-state, spherical helical assemblies (fig. S10).

We then investigated the structure of our synthesized OSCA materials. Polarized optical microscopy (POM) revealed characteristic Maltese cross textures in the fully oriented OSCA materials, demonstrating a radial configuration of the long axes of CLCs, which was attributed to the vertical anchoring of the CLC helix induced by PVA (Fig. 2E and fig. S11). X-ray diffraction (XRD) analysis revealed a broad peak near 2θ ≈ 21° and the absence of diffraction peaks in the low-angle region, indicating the presence of chiral nematic order within the polymerized OSCA materials (Fig. 2F and fig. S12) (34). To explore molecular packing, we further used grazing-incidence wide-angle x-ray scattering (GIWAXS) to compare the prepolymerized assemblies with the fully polymerized OSCA materials (35, 36). A distinct scattering peak at q ≈ 1.45 Å⁻¹ confirmed the formation of the aligned OSCA materials with molecular ordering instantly locked by ultraviolet-induced photopolymerization (Fig. 2, G and H, and fig. S13). In addition, we examined the thermal stability of the OSCA materials and found no obvious thermal decomposition when heated to ~150°C, evidencing their suitability for stable use in practical applications (fig. S14). These high-quality constrained helical superstructures guarantee the achievement of highly asymmetric circularly polarized emission.

Chiral-related photophysical behavior of OSCA

We then qualified the chiroptical properties of synthesized OSCA materials (Fig. 3A). With dye-doped OSCA as a typical example, diffuse reflectance circular dichroism (DRCD) spectra revealed that they exhibited exceptionally high mirror-image signals (above 8°), with both the wavelength and sign tunable by adjusting the ratio and configuration of the chiral dopants (fig. S15). The chirality of the OSCA materials enabled them to exhibit distinct selective reflection under different handed polarizing filters (Fig. 3B). Photoluminescence (PL) spectra showed that the OSCA materials doped with different dyes emitted bright red, green, and blue fluorescence, respectively (figs. S16 and S17). The strong chiroptical signals and bright emission are crucial for achieving circularly polarized emitters with high g_lum values.

Fig. 3. Chiroptical properties and circularly polarized emission of OSCA materials.

(A) Schematic diagram showing the emission of LH and RH circularly polarized light from OSCA materials, where σ⁺ and σ⁻ mean LH and RH circular polarizations, respectively. (B) POM images of multicolor OSCA materials with RH (left column) and LH (right column) rotation under RH (LH) circular-polarizing filters (CPFs), displaying distinct polarization reflection differences, indicating the strong chiral effects of the materials. Scale bar, 100 μm. B, blue; G, green; R, red. (C) Circularly polarized emission spectra of LH and RH OSCA materials modulated by different dye dopings. (D) Intensity of OSCA material luminescence sequentially passing through a quarter-wave plate (QWP) and a linear polarizer as a function of the angle between the linear polarizer and the optical axis, for both with and without the quarter-wave plate. (E and F) Dependence of luminescent intensity on polarization angle and wavelength for the RH (E) and LH (F) OSCA materials. (G) Schematic of optical path for visualizing the circular polarization difference. (H) Three-dimensional PL spectra of LH green dye–doped OSCA material under LH (left column) and RH (right column) CPFs, showing obvious fluorescence intensity differences. (I) Photographs to image the circular polarization emission for OSCA materials with corresponding CPFs. Scale bars, 2 mm. Inserts show the partial enlarged images. Scale bars, 400 μm.

We quantified the circularly polarized emission capability of the OSCA materials and achieved the maximum |g_lum| value of up to 0.9 (Fig. 3C and fig. S18), which was attributed to the strong coupling between the dye emission peak and the well-ordered helical structure of the CLC (fig. S19). To further confirm the circularly polarized characteristics of the OSCA materials, we used a fiber-coupled spectrometer to measure the transmission of light, showing that the emitted light maintained a constant intensity through a linear polarizer (Fig. 3D). When passed through a quarter-wave plate before the polarizer, it was converted into orthogonally linear polarized light (Fig. 3, E and F). These results evidence that the OSCA materials emit high-quality circularly polarized light. Notably, the obtained materials showed simultaneous improvements in g_lum values, processability, and robustness, fulfilling the requirements for polarized optical mappers with enhanced durability and signal clarity.

We also demonstrated the circular polarization effect by measuring the emission intensity through left-handed (LH) and right-handed (RH) circular-polarizing filters (Fig. 3G). Three-dimensional fluorescence spectra showed that, for example, the LH green-emitting material exhibited an obvious brightness difference when passed through the circular-polarizing filters (Fig. 3H). The distinct brightness contrast of the OSCA materials was visualized using a photometer (Fig. 3I) when building up to polarized optical mappers.

Information-encoding performance of polarized optical mappers

We embedded OSCA materials seamlessly into polymer matrices to construct polarized optical mappers, with the OSCA randomly distributed to generate information entropy (figs. S20 and S21). To evaluate the optical recognition capabilities, we fabricated over 50 independent mappers and acquired images through circular-polarizing filters for each mapper in two separate measurements. These images were then processed to binary signals for further calculations (Fig. 4A).

Fig. 4. Performance and authentication of polarized optical mappers.

(A) Description of the bit extraction process, including (i) obtaining raw LH and RH brightness images, (ii) subtracting LH and RH images to reduce noise, (iii) binarization, and (iv) digitization and extraction of response bits. (B) Heatmap of similarity obtained from over 50 unique mappers created using the same method. (C and D) Interdevice Hamming distance is used to characterize the device uniqueness of the mappers integrated with (C) and without (D) circular polarization. For (C), the Gaussian fit of the histogram returns μ = 0.49684 and SD σ = 0.04103. The degree of freedom (i.e., the number of independent variables) of 0.49684 × (1–0.49684) ÷ 0.04103² ≈ 148 results in an encoding capacity of 2¹⁴⁸. For (D), μ = 0.42992 and SD σ = 0.05130, with the calculated encoding capacity being 2⁹³. The intradevice Hamming distance is used to characterize the readout reproducibility (i.e., reliability). Each mapper was measured twice. The clear separation between the interdevice and intradevice distribution results indicates a very low misread probability. (E) Histogram of the encoding capacity of polarized optical mappers and optical mappers, showing that the introduction of circular polarization greatly enhances the encoding capacity of the mappers. (F) Recognition accuracy for the same sample (i.e., intradevice) and between different samples (i.e., interdevice) as the threshold varies, using the SSIM method. (G) Heatmap of similarity values calculated by the SSIM model. (H) SSIM results between two measurements of the same sample and between different samples.

We performed a statistical analysis of the mapper parameters, including uniqueness, bit uniformity, and reliability. Taking a 16 pixel–by–16 pixel binary encoding as an example, the results showed nearly ideal uniqueness (0.4968), confirming that each mapper can be distinctly identified from others. The bit uniformity of 0.4917 indicated high randomness, and the reliability of 0.9355 ensured that the mappers could consistently reproduce the same response bits under identical verification conditions. In addition, the high similarity between two measurements of the same mapper allows for easy distinguishment between true and false ones (Fig. 4B). These results, which approach theoretical values, demonstrate that the micropatterns and encoding of our polarized optical mappers are particularly distinct and provide robust responses to repeated challenges.

Because of the randomness and variation in the images exhibited by each mapper, we also implemented higher-level encoding for each pixel (e.g., quaternary, octal, hexadecimal, etc.). The results also demonstrated similar close-to-theoretical uniqueness, bit uniformity, and reliability (figs. S22 to S24). In addition, we calculated the encoding capacity of the polarized optical mappers, revealing that the integration of circularly polarized emission enhanced the encoding capacity by a factor of 2⁵⁵ (Fig. 4, C to E). This demonstrates that the incorporation of circular polarization considerably‌ offers resistance against external attacks such as brute-force cracks, side-channel vulnerabilities, and modeling threats (figs. S25 to S27).

Furthermore, we performed supplementary verification using the open-source structural similarity index measure (SSIM) algorithm (37), which compared image pairs and recorded similarity results (fig. S28). With an appropriately selected decision threshold, the SSIM achieved an accuracy nearly identical to the perfect of 100% (Fig. 4F). We calculated the similarity of the mappers, consistently observing a substantial difference between intra- and intercorrelations, indicating high reliability in the identification process (Fig. 4, G and H).

Practicality of polarized optical recognition

Our OSCA-based polarized optical mappers, integrated with macroscopic patterning techniques, enable practical applications (Fig. 5A). By printing OSCA-based polymer ink, we formed scalable patterns that carry circularly polarized signals, meaning that the patterns created using OSCA materials for mappers are deterministic at the macroscopic scale, allowing easily readable patterned information about the object’s surface. In addition, the arrangement of OSCA materials within each mapper is random, ensuring that the microscopic patterns of each mapper are unique and identifiable, allowing for reliable authentication of objects carrying the mappers (Fig. 5B). We also designed a portable information-recognition setup for the practical use (fig. S29).

Fig. 5. Far-field identification and near-field authentication.

(A) Schematic illustration of the application of polarized optical mappers in practical scenarios. (B) Schematic diagram of the far-field recognition and near-field authentication processes. First, we used a designed setup to recognize circularly polarized signals at a distance, thereby obtaining the corresponding macroscopic pattern information; furthermore, by measuring the microscopic patterns of each mapper, unique authentication can be ensured. The bottom right photograph shows a patterned polarized optical mapper printed using direct ink writing. Scale bar, 2 cm. (C) Measured SSIM results obtained from different mappers in real-world scenarios, demonstrating a clear interdevice difference. (D) Demonstration of the actual application of the polarized optical mapper on a door (scale bar, 3 cm), as well as the image of the mapper obtained using the designed setup (the insert; scale bar, 5 mm). (E) Comparison of the SSIM results obtained by comparing images from (D) with two other mapper images, revealing unique recognition. (F to I) Applying mappers to arbitrary objects, including curved lampposts (F) (scale bar, 5 cm), rough walls (G) (scale bar, 5 cm), wooden objects (H) (scale bar, 5 cm), and chip devices (I) (scale bar, 1 cm). Scale bars, 5 mm (inserts). (J) Real-world application of the mapper in an urban landscape for unique physical-digital linking to display distinct information. The size of each mapper is 1.5 cm by 1.5 cm.

We first achieved far-field reading of the mapper patterns, where the circular polarization contrast enabled the subtraction of LH and RH circularly polarized images to reveal the mapper pattern with a maximum contrast by removing the background (fig. S30). Furthermore, we demonstrated near-field reading of detailed polarized optical responses at the resolution of a single OSCA. We fabricated 30 mappers and examined their similarities, with authentication results confirming that the false-positive rate approached zero (Fig. 5C). In addition, we demonstrated the mapper’s practical application and assessed its performance robustness under various conditions (e.g., variable lighting, optical misalignment, motion drift, and surface contamination) (Fig. 5D and fig. S31). The recognition system consistently maintained high SSIM values, confirming the reliability and uniqueness of the mapper for practical authentication and information readouts (Fig. 5E).

Last, we evidenced the versatility of polarized optical mappers on various target surfaces, such as curved lampposts, rough walls, wooden objects, and chip devices (Fig. 5, F to I), for unique identification and function as internet of things hardware interfaces. In complex environments such as urban landscapes, background subtraction also minimizes false positives, enabling accurate far-field classification and near-field recognition (Fig. 5J). By combining these functionalities within a single device, our made mappers offer a valuable tool for effortless classification and secure authenticity verification, making them promising for physical-digital integration in smart cities, intelligent internet of things systems, and beyond.

DISCUSSION

In this work, we proposed a solidified-in-place helical assembly strategy, coupled with an automated in situ synthesis and monitoring platform, for fabricating durable, processable OSCA materials endowed with strong circularly polarized emission. By constructing random arrays of OSCA materials as optical media, we engineered polarized optical mappers that exhibited enhanced resistance to environmental interference and supported complex optical responses. We evaluated the optical recognition performance of these mappers, demonstrating near-ideal uniqueness, bit uniformity, and reliability, thereby ensuring robust encoding for identification. Furthermore, we demonstrated that the encoding capacity of the mappers was highly enhanced by the introduction of circular polarization, providing higher level against external threats. We also used the open-source SSIM model for supplementary verification, revealing considerable intra- and interdevice correlation differences that enable precise authentication. Last, we showcased the application of the mappers in real-world scenarios, where it provides reliable object authentication and information readout, demonstrating promising applications in complex environments such as smart cities and the internet of things. With its unique circular polarization signal encoding and anti-interference capability, polarized optical mapper offers an innovative solution for optical validation and efficient recognition.

MATERIALS AND METHODS

Materials

The nematic liquid crystal host (E7, n = 1.747, T_c = 60°C), chiral dopants (R/S5011), and the reactive monomer {1,4-bis-[4-(3-acryloyloxypropyloxy)benzoyloxy]-2-methylbenzene, RM257, >98.0%} were purchased from Shijiazhuang Yesheng Chemical Technology Co. Ltd. The photoinitiator (2,2-dimethoxy-2-phenylacetophenone, I-651, 99%) was purchased from ADAMAS-BETA. The fluorescent dyes 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (95%), 3-(1H-benzimidazol-2-yl)-7-(diethylamino)-2H-chromen-2-one (98%), and 7-diethylamino-4-methylcoumarin (99%) were purchased from Sigma-Aldrich. The Eu complex {Eu(BMDMB)₃·Phen, BMDMB = 1-[4-(1,1-dimethylethyl)phenyl]-3-(4-methoxyphenyl)-1,3-propanedione, Phen = 1,10-phenanthroline hydrate} was purchased from Hangzhou Aitong trading Co. Ltd. PVA (1788) was purchased from Shanghai Aladdin Biochemical Technology Co. Ltd.

Configuration of CLC precursor assemblies.

First, the nematic liquid crystal E7, chiral dopant R/S5011, and luminescent guests (including fluorescent dyes, Eu complexes, and InP/ZnSeS/ZnS quantum dots) were dissolved in n-hexane. The solvent was then evaporated in a drying oven at 60°C to obtain cholesteric liquid crystals. The chiral dopants were incorporated at a ratio of 2.8 to 3.8 wt % relative to the nematic liquid crystal to control the photonic bandgap in the visible light. The amount of luminescent guest added was 0.5 to 2 wt %. To achieve a robust and durable chiral helical structure, precursor assemblies for microsphere formation were prepared by mixing 69.65 wt % cholesteric liquid crystal, 29.85 wt % reactive mesogen of RM257, and 0.5 wt % photoinitiator of I-651.

Construction of in situ automated synthesis and monitoring platform

To achieve the automated synthesis of OSCA materials, we developed an in situ synthesis and monitoring platform composed of control, injection, and monitoring modules. The injection module consists of two injection pumps (Yanhang Power Technology Co. Ltd.) and a T-shaped droplet generation chip (Wenhao Microfluidic Technology Co. Ltd.). The monitoring module is based on a microscope (Mshot MP41) equipped with an eyepiece, objective lenses, and a camera. The control module is integrated with a computer connected to both the injection pumps and the microscope.

Synthesis of OSCA microdroplets

The dispersed phase consists of the CLC precursor assemblies, while the continuous phase is a 5 wt % PVA solution. Using the synthesis platform, the dispersed phase is sheared into microdroplets by the continuous phase. The flow rates of the dispersed and continuous phases are typically set to 0.3 and 200 μl/min, respectively. The microdroplets are collected into a 5 wt % PVA solution and incubated for a period to improve the alignment of the liquid crystal molecules. Subsequently, the microdroplets are exposed to ultraviolet light for 30 min in an ultraviolet curing box (Shenzhen Muxi Automation Equipment Co. Ltd.) to initiate polymerization, yielding solid and durable materials.

Fabrication of polarized optical mappers

To fabricate a large number of polarized optical mappers, the prepared OSCA materials were dispersed into a 10% PVA solution to form a mixed ink. The mixed ink was then cast onto plasma-cleaned glass slides, and the water was evaporated under ambient conditions. The OSCA materials were randomly dispersed within the PVA film, which was subsequently peeled off from the glass substrate to obtain the mappers, each ~1.5 cm by 1.5 cm in size.

Patterned polarized optical mappers were fabricated by printing the dispersed OSCA-mixed ink onto the glass substrate using a microelectronic printer (MP1100, Prtronic). By adjusting the printing air pressure and speed, the ink release rate could be precisely controlled.

Characterizations

The three-dimensional images of the polarized optical mappers were processed and visualized using a nano x-ray microscope (Zeiss, Xradia 520 Versa) and its image processing software (Dragonfly Pro, ORS). The morphology of the microdroplet evolution and OSCA materials, as well as the alignment of the liquid crystal molecules, was observed in both reflection and transmission modes using an optical microscope equipped with a cross-polarizer filter (Mshot MP41). The molecular structure and stacking information within the OSCA materials were analyzed by XRD (Rigaku) and GIWAXS (Xeuss 2.0, Xenocs). Reflectance spectra were measured using an ultraviolet/visible/near-infrared spectrophotometer (3700 DUV, Shimadzu). Two-dimensional and three-dimensional fluorescence spectra were measured using a fluorescence spectrometer (F-4700, Hitachi), respectively. The fluorescence lifetime of the OSCA materials was measured using a steady-state and time-resolved fluorescence spectrometer (Fluorolog-3-Tau and DeltaFlex). DRCD spectra were recorded on a circular dichroism spectrometer (J-1700, JASCO). Circularly polarized luminescence spectra were recorded on a circularly polarized fluorescence spectrometer (CPL-300, JASCO); the instrument was calibrated using a 0.06% (w/v) aqueous solution of ammonium d-10-camphor sulfonate. The microscopic morphology of the OSCA materials and cross section of the mappers were captured using a Schottky field emission scanning electron microscope (Schottky FE-SEM, GeminiSEM 500). The brightness differences of the OSCA materials within the mappers under different polarizers were measured using a photometer (CX1000, Hopoocolor). The circular polarization characteristic was demonstrated by converting the circularly polarized light emitted by the OSCAs to linearly polarized light using a quarter-wave plate (350 to 850 nm; Thorlabs). The direction of linear polarization was then determined using a rotating polarizer (400 to 700 nm; Thorlabs).

Supplementary Materials

The PDF file includes:

Supplementary Text

Figs. S1 to S31

Legend for movie S1

Other Supplementary Material for this manuscript includes the following:

Movie S1