CN-121995645-A - Laser speckle suppression device, device and optical equipment

CN121995645ACN 121995645 ACN121995645 ACN 121995645ACN-121995645-A

Abstract

The application discloses a laser speckle suppression device, a device and display equipment, wherein the laser speckle suppression device comprises a piezoelectric ceramic element and a transparent solid element, the center of the piezoelectric ceramic element is provided with a hole, the transparent solid element and the center hole of the piezoelectric ceramic element are the same in shape and are not adhered to the inner side of the piezoelectric ceramic element, and the piezoelectric ceramic element comprises at least one piezoelectric ceramic body and an electrode. The application generates ultrasonic wave through the piezoelectric ceramic element, the ultrasonic wave is transmitted along the radial direction by taking the transparent solid element as a medium, when laser irradiates the transparent solid element with ultrasonic wave action, raman-Ness diffraction is generated, and the phase of diffracted light is modulated by ultrasonic wave in time and space, thereby reducing the coherence of the laser and achieving the purpose of inhibiting speckle.

Inventors

DING YAN
LI YONGQI
CUI YI

Assignees

陕西蔚影激光科技有限公司

Dates

Publication Date: 20260508
Application Date: 20240108

Claims (10)

1. A laser speckle suppression device, comprising: a piezoelectric ceramic element and a transparent solid element; Wherein the piezoelectric ceramic element is provided with a central opening; The transparent solid element has the same shape as the central hole of the piezoelectric ceramic element, and is not adhered in the hole of the piezoelectric ceramic element: The piezoelectric ceramic element includes at least one piezoelectric ceramic body and an electrode.
2. The laser speckle suppression device of claim 1, wherein the thickness of the transparent solid element is less than or equal to the thickness of the piezoelectric ceramic element.
3. The laser speckle suppression device of claim 1, wherein the material of the transparent solid element is any one of glass, plastic, crystal, and transparent ceramic.
4. The laser speckle suppression device of claim 1, wherein a product of a thickness of the transparent solid element and a vibration frequency of the piezoelectric ceramic element satisfies a raman-ness diffraction condition.
5. The laser speckle reduction device of claim 1, wherein the at least one piezoceramic body is a radially polarized piezoceramic ring.
6. The laser speckle suppression device of claim 4, wherein the piezoelectric ceramic element comprises an outer diameter composite layer, a piezoelectric ceramic layer, and an inner diameter composite layer; wherein the piezoelectric ceramic layer is positioned between the outer diameter composite layer and the inner diameter composite layer; the inner diameter composite layer is positioned on one side close to the transparent solid element; The outer diameter composite layer is located on a side remote from the transparent solid element.
7. A laser speckle suppression device, characterized by comprising an excitation source and the laser speckle suppression device according to any one of claims 1-6; The excitation source is electrically connected with the piezoelectric ceramic element; the excitation source is used for driving the piezoelectric ceramic element to vibrate and generate ultrasonic waves.
8. The laser speckle suppression device of claim 7, wherein the excitation source comprises a signal generator and a power amplifier; the power amplifier is electrically connected with the signal generator and the piezoelectric ceramic element respectively; The signal generator is used for generating an original signal for driving the piezoelectric ceramic element; the power amplifier is used for amplifying the original signal to a preset threshold value to drive the piezoelectric ceramic element to vibrate and generate ultrasonic waves; The original signal is an alternating signal.
9. The laser speckle reduction device of claim 8, wherein the excitation source further comprises a duty cycle adjuster disposed between the signal generator and the power amplifier or between the power amplifier and the piezoceramic element; the duty ratio regulator is used for regulating the on-off of the electric signal output by the excitation source.
10. An optical device, comprising a laser light source module and the laser speckle suppression device according to claim 7, wherein laser light emitted from the laser light source module is transmitted out from a transparent solid element in the laser speckle suppression device.

Description

Laser speckle suppression device, device and optical equipment Technical Field The application relates to the technical field of projection equipment, in particular to a laser speckle suppression device, a laser speckle suppression device and an optical equipment. Background The laser display technology is a display technology which takes red, green and blue (RGB) three primary color lasers as light sources, can truly reproduce rich and gorgeous colors in the objective world, and provides more shocking expressive force. From the colorimetry perspective, the color gamut coverage rate of laser display can reach more than 90% of the color space which can be identified by human eyes, and is more than twice of the color gamut coverage rate of traditional display, so that the defect of the color gamut space of the prior three-generation display technology is thoroughly overcome, the perfect color reproduction of human history is realized, and people can see the truest and gorgeous world through a display terminal. However, when the laser light is diffusely reflected at the surface of the diffuser or passes through a transparent diffuser (e.g., frosted glass), a random distribution of light and dark spots, known as laser speckle (LASERSPECKLES), is observed in the light field at or near the diffuser surface. Laser speckle affects the viewing experience severely, so how to eliminate laser speckle on display screens is also one of the key directions of technical development in the field in recent years. To suppress laser speckle, an apparatus for suppressing speckle by ultrasonic vibration has been proposed. The device consists of a piezoelectric transducer and a distilled water tank, and the structure of the device is shown in figure 1. However, in the laser speckle suppression device shown in fig. 1, distilled water is used as an ultrasonic medium, and the projection device is an electronic device which depends on a circuit board, a control chip and the like to work, so that once the distilled water leaks, the circuit board and the control chip are damaged, and the projection device cannot work continuously. The description of the background art is only for the purpose of facilitating an understanding of the relevant art and is not to be taken as an admission of prior art. Disclosure of Invention Therefore, the embodiment of the invention aims to provide the laser speckle suppression device with higher practicability and reliability, and the purpose of suppressing the laser speckle is achieved by combining the piezoelectric ceramic element with the transparent solid element and using the transparent solid wafer as a transmission medium of ultrasonic waves, so that the problem of damage to a circuit board and a control chip caused by liquid leakage in the laser speckle suppression device can be solved. In a first aspect, the embodiment of the invention provides a laser speckle suppression device, which comprises a piezoelectric ceramic element and a transparent solid element, wherein the center of the piezoelectric ceramic element is provided with an opening, the transparent solid element and the center hole of the piezoelectric ceramic element are identical in shape, and the transparent solid element is adhered in the hole of the piezoelectric ceramic element in a seamless manner, and the piezoelectric ceramic element comprises at least one piezoelectric ceramic body and an electrode. Optionally, the thickness of the transparent solid element is less than or equal to the thickness of the piezoelectric ceramic element. Optionally, the material of the transparent solid element is any one of glass, plastic, crystal and transparent ceramic. Optionally, the product of the thickness of the transparent solid element and the vibration frequency of the piezoelectric ceramic element satisfies a raman-ness diffraction condition. Optionally, the at least one piezoceramic body is a radially polarized piezoceramic ring. The piezoelectric ceramic element comprises an outer diameter composite layer, a piezoelectric ceramic layer and an inner diameter composite layer, wherein the piezoelectric ceramic layer is positioned between the outer diameter composite layer and the inner diameter composite layer, the inner diameter composite layer is positioned on the side close to the transparent solid element, and the outer diameter composite layer is positioned on the side far away from the transparent solid element. In a second aspect, the embodiment of the present invention provides a laser speckle suppression device, where the laser speckle suppression device includes an excitation source and the laser speckle suppression device according to any one of the first embodiment, the excitation source is electrically connected to the piezoelectric ceramic element, and the excitation source is used to drive the piezoelectric ceramic element to vibrate and generate ultrasonic waves. Optionally, the excitation source comprises a signal generato