Using micro-projectors to realize large screen head-up display

Weng, Ching-Pao; Su, Guo-Dung John

doi:10.1117/12.929366

“…Due to the low energy efficiency, the image generated by LCD is not high enough to avoid the washout of the image. This issue cannot be solved by simply increasing the power of the backlight which will cause dramatic temperature increase of the display module [125]. Another issue with the LCD based HUD is the tradeoff between the display size and the volume of the system.…”

Section: Automotive Head-up Display (Hud) Reviewmentioning

confidence: 99%

“…A DMD based display module has the advantage of low power consumption, high energy efficiency, fast response time and long working life. A simple prototype of DMD based HUD has been developed in [125]. A commercial DMD based portable projector was used to generate the display image.…”

Section: Automotive Head-up Display (Hud) Reviewmentioning

confidence: 99%

Development of electrostatic actuators with large out-of-plane deflection and its application in scanning display

Chen¹

2021

Preprint

0

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Electrostatic out-of-plane microactuators have been widely used in applications of variable capacitors, optical attenuators, optical switches and scanning displays due to their small size, low cost, simple and diverse structure, low power consumption and high compatibility with semiconductor process. The large out-of-plane displacement of the microactuator with high reliability is preferred in order to increase the tuning range, tunability and the display size. However, the “pull-in” instability associated with conventional attractive-force electrostatic microactuators significantly limits the out-of-plane displacement and lowers the operation stability. A repulsive-force microactuator has been previously developed which can achieve large out-of-plane rotation and does not suffer from the “pull-in” instability. However, a larger rotation angle of the repulsive-force actuator is highly desired in order to improve its performance in the applications such as increasing the tunability and the scanning angle. In this thesis two novel repulsive-force actuators, i.e., two-row interdigitating-finger and two-width-finger (TWF) actuators are developed which output much larger out-of-plane rotation than the previous repulsive-force actuator without suffering from the “pull-in” instability. The mathematical models are established for both actuators using a hybrid approach. The actuators require only two thin layers and are suitable for surface micromachining process. The measured results show that the two microactuators can achieve rotation angles of 11.5° and 7.5° at 150 V respectively. The improvements are 100% and 35% in comparison to the previous repulsive-force actuator with the same size, stiffness and driving voltage. A 2D scanning micromirror has been developed and fabricated based on the two-row-finger (TRF) actuator. Experimental results show the micromirror has larger rotation angle and faster response speed than those of the micromirror driven by the previous repulsive-force microactuator. The vector scanning display based on the micromirror is demonstrated. An advanced display approach is developed to generate displays with less distortion and higher refreshing rate compared to the previous generic display approach. The automotive Head-up Display (HUD) based on the micromirror and advanced display approach has been constructed for both real and virtual image configurations, which has advantages of small size, low cost, large viewing angle and good visibility over those HUDs in the market.

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“…Due to the low energy efficiency, the image generated by LCD is not high enough to avoid the washout of the image. This issue cannot be solved by simply increasing the power of the backlight which will cause dramatic temperature increase of the display module [125]. Another issue with the LCD based HUD is the tradeoff between the display size and the volume of the system.…”

Section: Automotive Head-up Display (Hud) Reviewmentioning

confidence: 99%

“…A DMD based display module has the advantage of low power consumption, high energy efficiency, fast response time and long working life. A simple prototype of DMD based HUD has been developed in [125]. A commercial DMD based portable projector was used to generate the display image.…”

Section: Automotive Head-up Display (Hud) Reviewmentioning

confidence: 99%

Development of electrostatic actuators with large out-of-plane deflection and its application in scanning display

Chen¹

2021

Preprint

0

View full text Add to dashboard Cite

Electrostatic out-of-plane microactuators have been widely used in applications of variable capacitors, optical attenuators, optical switches and scanning displays due to their small size, low cost, simple and diverse structure, low power consumption and high compatibility with semiconductor process. The large out-of-plane displacement of the microactuator with high reliability is preferred in order to increase the tuning range, tunability and the display size. However, the “pull-in” instability associated with conventional attractive-force electrostatic microactuators significantly limits the out-of-plane displacement and lowers the operation stability. A repulsive-force microactuator has been previously developed which can achieve large out-of-plane rotation and does not suffer from the “pull-in” instability. However, a larger rotation angle of the repulsive-force actuator is highly desired in order to improve its performance in the applications such as increasing the tunability and the scanning angle. In this thesis two novel repulsive-force actuators, i.e., two-row interdigitating-finger and two-width-finger (TWF) actuators are developed which output much larger out-of-plane rotation than the previous repulsive-force actuator without suffering from the “pull-in” instability. The mathematical models are established for both actuators using a hybrid approach. The actuators require only two thin layers and are suitable for surface micromachining process. The measured results show that the two microactuators can achieve rotation angles of 11.5° and 7.5° at 150 V respectively. The improvements are 100% and 35% in comparison to the previous repulsive-force actuator with the same size, stiffness and driving voltage. A 2D scanning micromirror has been developed and fabricated based on the two-row-finger (TRF) actuator. Experimental results show the micromirror has larger rotation angle and faster response speed than those of the micromirror driven by the previous repulsive-force microactuator. The vector scanning display based on the micromirror is demonstrated. An advanced display approach is developed to generate displays with less distortion and higher refreshing rate compared to the previous generic display approach. The automotive Head-up Display (HUD) based on the micromirror and advanced display approach has been constructed for both real and virtual image configurations, which has advantages of small size, low cost, large viewing angle and good visibility over those HUDs in the market.

show abstract