Projection Display Device Using Dichroic Mirrors for Virtual Keyboard
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current projectors with minimal optical elements struggle to effectively project virtual keyboards and images, and there is a need for a compact, high-picture-quality display device that can utilize leakage light for virtual input functions.
Innovation Solution
A projection display device with first to third light sources, an image projection unit, and a color synthesizing unit that selectively transmits or reflects light to emit light towards the image projection unit while leaking a portion for a virtual keyboard, using dichroic mirrors to direct light towards both the image projection and virtual keyboard, and additional light sources for enhanced illumination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If a projector uses a minimal number of optical elements to reduce device size, then the device becomes more compact, but it struggles to effectively project both virtual keyboards and images
Solution Approach 1:
The optical system is segmented into separate functional paths: one for image projection and another for virtual keyboard projection. The color synthesizing unit divides light into different pathways using dichroic mirrors, allowing independent optimization of each function while maintaining compact overall structure.
Solution Approach 2:
The color synthesizing unit serves multiple functions simultaneously: it synthesizes colors for the image projection unit while also leaking light to the virtual keyboard. This multi-functional design eliminates the need for separate light sources and optical elements, reducing device size while maintaining both projection capabilities.
2Volume of moving object
If a projector uses a minimal number of optical elements to reduce device size, then the device becomes more compact, but picture quality deteriorates
Solution Approach 1:
Different optical paths are optimized for their specific functions: the image projection path receives synthesized light with appropriate color rendering, while the virtual keyboard path receives leaked light optimized for its projection requirements. This localized optimization maintains picture quality despite the compact design.
Solution Approach 2:
The system adjusts light parameters (intensity, color, direction) at different stages to optimize both picture quality and virtual keyboard visibility. By controlling the amount of light leaked to the virtual keyboard and adjusting the synthesis of light for the image projection unit, high picture quality is maintained while enabling additional functionality.
3Adaptability or versatility
If a color synthesizing unit leaks light for virtual keyboard projection, then virtual input function is enabled, but light loss increases
Solution Approach 1:
The light that would otherwise be wasted or require separate handling is intentionally leaked from the color synthesizing unit to enable the virtual keyboard function. This converts what would be energy loss into a useful resource, allowing the same light source to serve dual purposes without requiring additional light sources.
Solution Approach 2:
The color synthesizing unit is designed to perform both image synthesis and virtual keyboard illumination functions simultaneously. By making the unit multi-functional, the system eliminates the need for separate light sources, thereby reducing overall energy consumption despite the additional projection capability.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables the creation of a compact projection display device capable of projecting virtual keyboards and images with improved picture quality, utilizing leakage light for virtual input functions, enhancing user interaction and reducing device size.
Implementation Method 1
a color synthesizing unit for selectively transmitting or reflecting the light, not only to emit the light toward the image projection unit, but also to leak a portion of the light
Implementation Method 2
a first reflection mirror for reflecting the light leaked from the color synthesizing unit, to send the reflected light to the virtual keyboard
Implementation Method 3
a second reflection mirror for reflecting the image from the image projection unit such that the image from the image projection unit is projected in a direction reverse to a projection direction of the virtual keyboard
Implementation Method 4
a third reflection mirror for reflecting the keyboard image projected from the virtual keyboard such that the keyboard image is projected in a direction parallel to a projection direction of the image projection unit
Data Source
AI summary
A projection display device (100) capable of providing a virtual keyboard function to the user, using a light source of a pico projector, is discussed. According to an embodiment, the projection display device includes a light source unit (110) configured to emit lights; a light combining unit (120) configured to generate a leakage light from the lights emitted by the light source (110) unit and to selectively combine the lights from the light source unit (110); an image projection unit (130) configured to project an image using the combined light from the light combining unit (120); and a virtual input unit (140) configured to project an input unit image (150) using the leakage light from the light combining unit (120).