JPH0643422A - Electronic sunglasses - Google Patents

Abstract

PURPOSE:To change over transmittance width and absolute value according to applications and to lessen the eyes' fatigue by sticking synthetic resins into which a photochromic material is incorporated to at least either side of a film- like liquid crystal panel which is a lens part. CONSTITUTION:A liquid crystal cell is constituted by holding a nematic liquid crystal added with a proper amt. of a dextrorotatory chiral material between a film-like upper substrate 1 subjected to rubbing and a film-like lower substrate 2 by means of a seal 3. Further, the absorption axis of a polarizing plate 4 and the rubbing direction of the film-like upper substrate 1 as well as the absorption axis of a polarizing plate 5 and the rubbing direction of the film-like lower substrate 2 are aligned. The polarizing plates 4, 5 having 41% parallel transmittance and 98% degree of polarization are used for the polarizing plates 4, 5. The liquid crystal element is stuck to diethylene glycol bis-ally carbonate resin plates 8, 9 via adhesive layers 6, 7 from both sides. The photochromic material colors gradually and the transmittance changes between 10% and 20% if there are many UV rays in a high-illuminace place, such as skiing ground.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable transmittance electronic sunglasses utilizing the electro-optical effect of liquid crystal.

[0002]

2. Description of the Related Art The concept of sunglasses having variable transmittance using liquid crystal has been presented in the past. As a general concept, FIG. 1 described in JP-A-48-98846,
FIG. 3 described in JP-A-51-124936, FIG. 1 described in JP-A-62-127524, and JP-A-62-
5 and 7, as described in 40425, Showa 55-
Fig. 1 described in 95106, 59-1786
FIG. 18 described in FIG. 18 and FIG. 1 described in Japanese Utility Model Application Laid-Open No. 62-109137, and a combination of a liquid crystal panel which is a transmittance variable section, a power supply, a drive circuit, a control circuit, and a light detection section. It is known to make up electronic sunglasses.

[0003]

Conventionally, it has been shown that a guest-host type or a twisted nematic type is used for the variable transmittance portion of sunglasses utilizing the electro-optical effect of liquid crystal. From a fail-safe standpoint, it is currently difficult to realize a positive guest host, and the twisted nematic liquid crystal element is the closest to realizing electronic sunglasses.

When a twist nematic type liquid crystal element is used for the transmittance varying portion, ideally, when the absorption axes of two polarizing plates are orthogonal, the change width of the transmittance is 50 when the voltage is applied to the liquid crystal element or when it is released. It is between 0% and 0%. However, in reality, due to problems such as polarization efficiency, the range of transmittance change is between 35% and 3%.

Further, a problem in using the twisted nematic type liquid crystal element is the viewing angle dependence on the liquid crystal element. When the absorption axes of the two polarizing plates are made orthogonal,
It has a large visual angle dependency, and when used as sunglasses,
The unevenness of the transmittance depending on the angle at which the liquid crystal element is viewed by the eyeball is very noticeable. In order to solve this point, it is necessary to devise such as increasing the transmittance by setting the angle between the absorption axis and the rubbing direction of the substrate to 60 to 80 degrees or 100 to 120 degrees. When the viewing angle dependency is improved in this way,
The transmittance is increased as a whole, and there is a new problem that the sunglasses are not satisfactory even when the transmittance is low. In addition, regardless of guest-host type or twisted nematic type, when a liquid crystal element whose transmittance changes instantaneously is used for sunglasses, the transmittance changes rapidly, so that "eyes get tired" and "a feeling of discomfort" occurs. There was a problem.
This is remarkable when the transmittance is high from low.

Therefore, the present invention solves such a problem, and its object is to change the transmittance range and the absolute value which are variable in the transmittance in the electronic sunglasses using the film-like liquid crystal panel. To get electronic sunglasses that will not tire your eyes.

[0007]

SUMMARY OF THE INVENTION The present invention provides an electronic sunglasses with a variable transmittance, which uses a film-like liquid crystal panel,
It is characterized in that a synthetic resin containing a photochromic substance is attached to at least one of the film-like liquid crystal panels as the lens portion.

The synthetic resin to be attached to the film type liquid crystal panel may be dispersed with a halogen compound containing an inorganic silver atom as a photochromic substance, or may be impregnated with an organic spirooxazine compound. You can At this time, it is important to adjust the concentration of the photochromic substance in consideration of the concentration when the photochromic substance is colored. An adhesive or an adhesive may be used to bond the film-shaped liquid crystal panel and the synthetic resin. However, it is necessary to select one that does not impair the transparency. The synthetic resin may be a flat plate or a prescription lens.

[0009]

The present invention will be described in detail below with reference to examples, but the present invention is not limited thereto.

(Embodiment 1) FIG. 1 is a sectional view of a lens portion in one embodiment of the present invention. The liquid crystal cell has a structure in which a nematic liquid crystal to which an appropriate amount of a dextrorotatory chiral substance is added is sandwiched by a seal 3 between a film-shaped upper substrate 1 rubbed in the A direction and a film-shaped lower substrate 2 rubbed in the B direction. . The angle θ formed by the rubbing direction A and the rubbing direction B is 70 degrees. Further, the absorption axis of the polarizing plate 4 and the rubbing direction A of the film-shaped upper substrate are aligned with each other, and the absorption axis of the polarizing plate 5 and the rubbing direction B of the film-shaped lower substrate are aligned with each other. A polarizing plate having a parallel transmittance of 41% and a polarization degree of 98% was used. The transmittance characteristics of this liquid crystal element were 8% when voltage was applied and 40% when voltage was released.

In this example, this liquid crystal element was bonded to both sides of the diethylene glycol bisallyl carbonate resin plates 8 and 9 obtained as follows via adhesive layers 6 and 7.

1,3,3-as a photochromic substance
Trimethylpyro [indolino-2,3 naphtho [2,1-
b] (1,4) -oxazine] was made into a 5% solution of diethylene glycol. A 1 mm thick diethylene glycol bisallyl carbonate resin plate was added to this solution at 110 ° C. for 3 days.
It was immersed for 0 minutes.

As the adhesive, a transparent two-component epoxy adhesive was used.

The liquid crystal element thus obtained had the following transmittance.

When used in a vehicle such as a drive, ultraviolet rays are blocked by the windshield and the photochromic substance is not colored. Therefore, the transmittance is 40% to 80%
Varies between.

If there is much ultraviolet light in a place with high illuminance such as skiing,
The photochromic material is gradually colored and 10% to 20%
Varies between%.

The change width of the transmittance can be set arbitrarily depending on the time of immersing the photochromic substance.

[0018]

When a photochromic substance is not used, it is difficult to provide two or more kinds of transmittance variation ranges for driving and skiing in one electronic sunglasses. By using a photochromic substance together, it is possible to obtain the transmittance setting according to the situation by the light amount and the intensity of ultraviolet rays. In addition, the characteristics of electronic sunglasses, whose transmittance changes instantly, have been utilized to make it extremely easy to use. In addition, the liquid crystal responds instantly, and then the photochromic substance responds to it, so that eye fatigue is greatly reduced.

The present invention can be applied to sunglasses used in various environments such as driving and skiing.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a lens portion structure of the present invention.

[Explanation of symbols]

 1 Upper substrate 2 Lower substrate 3 Seal 4 Polarizing plate 5 Polarizing plate 6 Adhesive layer 7 Adhesive layer 8 Synthetic resin plate 9 Synthetic resin plate

Claims (1)

[Claims] 1. A variable transmittance electronic sunglasses using a film type liquid crystal panel, wherein a synthetic resin containing a photochromic substance is bonded to at least one of the film type liquid crystal panel which is a lens part. And electronic sunglasses.