Organic Light Emitting Diodes (OLEDs) are used to create digital display in many devices. What are the advantages of OLED displays over Liquid Crystal displays ? 1. OLED displays can be fabricated on flexible plastic substrates. 2. Roll-up displays embedded in clothing can be made using OLEDs. 3. Transparent displays are possible using OLEDs. Select the correct answer using the code given below :

Defines and distinguishes flexible plastic materials (e.g., flexible plastic sheets, covers, pouches), showing that plastics exist in flexible-sheet form suitable as substrates.

A student could combine this with the fact that display substrates are thin sheets to hypothesize that flexible plastic sheets might serve as display substrates and then check materials used in OLED/LCD manufacturing.

Notes that replacing a glass slab with a transparent plastic slab changes optical effects, implying transparent plastics can function similarly to glass in optical devices.

Using the basic fact that displays require transparent substrates, a student could infer transparent plastics might substitute for glass in display construction and investigate whether OLEDs can be deposited on such plastics.

Describes commonplace use of flexible plastics as insulating coverings on wires, demonstrating plastics can be used reliably in electrical/electronic contexts and in flexible form.

A student could extend this to ask whether similar electrical/thermal/chemical properties allow plastic substrates to host thin-film electronic layers used in OLEDs versus LCDs.

States that synthetic polymers (plastics) are affected by solar radiation and often require stabilizers or surface treatments for durability.

A student could use this to anticipate durability challenges for plastic-display substrates (e.g., UV stability, treatments) when comparing long-term performance of flexible plastic OLEDs vs glass-based LCDs.

Textile manufacture is globally widespread and clothing is a basic need, implying large potential demand for innovations embedded in clothing.

A student could combine this market ubiquity with knowledge of flexible electronics to judge commercial incentive for roll-up wearable displays.

Mentions Light Emitting Diode (LED) lamps as a modern light source; LEDs are an emissive technology like OLEDs (both produce their own light).

Knowing LEDs are emissive, a student could infer OLEDs (also emissive) might not need bulky backlights, a property useful for flexible/rollable displays.

Defines luminous objects as those that emit their own light and notes how light interacts with materials (transparent/translucent/opaque).

Using the idea of self-emission and light transmission, a student could reason that an emissive thin film display could function when laminated into fabrics unlike transmissive LCDs requiring backlighting and polarizers.

Notes higher cost of LED is a hindrance to wider use, showing cost is a practical barrier to adopting newer lighting/display tech.

A student could extend this to consider cost trade-offs for OLEDs in clothing vs flexible LCDs — economic feasibility affects adoption of roll-up displays.

States technology applies scientific knowledge to make production easier and gives examples of tech enabling new capabilities.

A student could take this general rule to consider flexible electronic manufacturing advances (e.g., printable OLEDs) that would enable embedding roll-up displays into garments.

Defines transparent materials as those through which light passes almost completely — establishes what 'transparent' means for a display.

A student could ask whether a display's layers and light sources can be arranged so most ambient light still passes through while the display also emits/controls light.

Summarises differences between transparent, translucent and opaque materials and notes some transparent objects can create faint shadows — useful for thinking about partial transparency in devices.

Use this to consider degrees of transparency for a display (fully vs partly transparent) and whether active components would make it translucent or still largely transparent.

Gives the example of looking through a flat transparent glass window pane where objects look the same — shows how a simple transparent sheet can allow undistorted viewing.

Compare a plain transparent pane to a multi-layer display stack to infer whether adding emitting layers could preserve window-like transparency.

Describes light rays changing direction at surfaces separating transparent media — highlights that adding layers/interfaces affects light transmission.

A student could consider how multiple thin layers in a display (substrates, electrodes) might refract/reflect light and thus reduce transparency unless designed to minimise such effects.

Notes that refraction effects depend on the pair of media — indicates optical behaviour varies with materials used in layered devices.

Apply this to think about choosing materials with similar refractive indices for display layers to reduce visible distortion and improve transparency.