High tilt angle FLC mixture for TIR switching devices

Details High tilt angle FLC mixture for TIR switching devices High tilt angle FLC mixture for TIR switching devices

1991-06-27

1994-05-10

Tucker, Philip

Compositions

Liquid crystal compositions

Containing nonsteryl liquid crystalline compound of...

560 73, C09K 1912, C07C 6976

Patent

active

053105028

ABSTRACT:
The invention provides a series of ferroelectic smectic liquid crystal compounds, FLC, of wide tilt angle and mixtures formulated from them that are useful for high speed modulation or switching of optical radiation. Such FLC mixtures are useful in total internal reflection, TIR switching devices. In such TIR switches, an applied DC voltage rotates the molecules through about a 90.degree. angle which changes the perceived refractive index at the FLC layer and permits rapid optical switching. For an FLC crystal material to be useful in such a device it must possess a value of molecular tilt angle .theta. of approximately 45.degree., since the dipole molecule rotates through an angle of about 2 .theta. upon application of a DC field to the cell. This requirement for a large molecular tilt angle greatly limits the compounds and mixtures thereof which can be employed in such TIR devices.
The smectic FLC compounds and mixtures thereof of the present invention provide for TIR switches that exhibit high contrast ratios ( <1,000:1). They can also provide in such switch, 2-position bistable beam deflection. That is, if the electric field of the TIR switches is shut off, the smectic FLC compounds will hold the molecular tilt angle existing at that time without requiring an applied electric field (to hold such pattern) unlike their nematic LC predecessors.

REFERENCES:
patent: 4834907 (1989-05-01), Inoue et al.
patent: 4966727 (1990-10-01), Ichihashi et al.
patent: 5076962 (1991-12-01), Furukawa et al.
patent: 5114614 (1992-05-01), Emoto et al.

Affiliated with

Also associated with

Rating

High tilt angle FLC mixture for TIR switching devices does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with High tilt angle FLC mixture for TIR switching devices, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and High tilt angle FLC mixture for TIR switching devices will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2411404