LASER LIGHT DETECTION TOOL

Abstract

The present invention aims to provide a laser light detecting device capable of easily detecting laser light irradiation. Provided is a laser light detecting device capable of detecting laser light irradiation, including: a luminescent sheet containing a thermoplastic resin and a luminescent material that is to be excited by laser light to emit visible light.

Claims

1. A laser light detecting device capable of detecting laser light irradiation, comprising a luminescent sheet containing a thermoplastic resin and a luminescent material that is to be excited by laser light to emit visible light.

2. The laser light detecting device according to claim 1, wherein the luminescent material emits light by visible laser light having a wavelength of 380 to 750 nm.

3. The laser light detecting device according to claim 1, wherein the luminescent material emits light by ultraviolet laser light having a wavelength of 380 nm or shorter.

4. The laser light detecting device according to claim 1, wherein the luminescent material emits light by infrared laser light having a wavelength of 750 nm or longer.

5. The laser light detecting device according to claim 1, which has a laminated structure including a transparent plate and the luminescent sheet.

6. The laser light detecting device according to claim 1, which has a structure in which the luminescent sheet is interposed between a pair of transparent plates.

7. The laser light detecting device according to claim 1, further comprising a detection unit configured to detect laser light irradiation.

8. The laser light detecting device according to claim 7, further comprising a notification unit configured to provide notification when the detection unit detects a laser.

9. The laser light detecting device according to claim 8, wherein the notification unit is configured to stop providing notification when the detection unit no longer detects laser light.

Description

DESCRIPTION OF EMBODIMENTS

[0084] The present invention is more specifically described in the following with reference to, but not limited to, examples.

Example 1

(1) Preparation of Eu(TFA).SUB.3.Phen

[0085] Europium acetate (Eu(CH.sub.3COO).sub.3) in an amount of 12.5 mmol was dissolved in 50 mL of distilled water. To the solution was added 33.6 mmol of trifluoroacetylacetone (TFA, CH.sub.3COCH.sub.2COCF.sub.3), and the mixture was stirred at room temperature for 3 hours. The mixture was filtered to obtain precipitated solid. The precipitated solid was washed with water, and recrystallized using methanol and distilled water to give Eu(TFA).sub.3(H.sub.2O).sub.2. Then, 5.77 g of the resulting complex (Eu(TFA).sub.3(H.sub.2O).sub.2) and 2.5 g of 1,10-phenanthroline (phen) were dissolved in 100 mL of methanol, followed by heating under reflux for 12 hours. After 12 hours, methanol was distilled off under reduced pressure, thereby obtaining a white product. The white product powder was washed with toluene so that unreacted materials were removed by suction filtration. Subsequently, toluene was distilled off under reduced pressure, thereby preparing a powder. Through recrystallization using a solvent mixture of toluene and hexane, Eu(TFA).sub.3phen was obtained.

(2) Preparation of Luminescent Sheet

[0086] To 40 parts by weight of triethylene glycol di-2-ethylhexanoate (3GO) as a plasticizer were added 0.2 parts by weight of Eu(TFA).sub.3phen as a luminescent material and acetylacetone magnesium at a final concentration of 0.036 phr as an adhesion modifier, whereby a luminescent plasticizer solution was prepared. The entire amount of the plasticizer solution obtained and 100 parts by weight of polyvinyl butyral (PVB, degree of polymerization: 1,700) were sufficiently mixed and kneaded using a mixing roll to prepare a resin composition.

[0087] The obtained resin composition was extruded using an extruder to provide a luminescent sheet having a thickness of 760 m.

(3) Production of Laser Light Detecting Device

[0088] The obtained luminescent sheet was interposed between a pair of clear glass plates (thickness: 2.5 mm, 30 cm in length30 cm in width) to prepare a laminate. The laminate was pressed under vacuum at 90 C. for 30 minutes to be press-bonded using a vacuum laminator. The press-bonded laminate was subjected to further 20-minute press-bonding under 14 MPa at 140 C. using an autoclave, thereby obtaining a laser light detecting device having a laminated glass structure.

Example 2

[0089] Terbium acetate (Tb(CH.sub.3COO).sub.3) in an amount of 12.5 mmol was dissolved in 50 mL of distilled water. To the solution was added 33.6 mmol of trifluoroacetylacetone (TFA, CH.sub.3COCH.sub.2COCF.sub.3), and the mixture was stirred at room temperature for 3 hours. The mixture was filtered to obtain precipitated solid. The precipitated solid was washed with water, and recrystallized using methanol and distilled water to give Tb(TFA).sub.3(H.sub.2O).sub.2. Then, 5.77 g of the resulting complex (Tb(TFA).sub.3(H.sub.2O).sub.2) and 2.5 g of 1,10-phenanthroline (phen) were dissolved in 100 mL of methanol, followed by heating under reflux for 12 hours. After 12 hours, methanol was distilled off under reduced pressure, thereby obtaining a white product. The white product powder was washed with toluene so that unreacted materials were removed by suction filtration. Subsequently, toluene was distilled off under reduced pressure, thereby preparing a powder. Through recrystallization using a solvent mixture of toluene and hexane, Tb(TFA).sub.3phen was obtained.

[0090] A luminescent sheet and a laser light detecting device were produced as in Example 1 except that Tb(TFA).sub.3phen was used instead of Eu(TFA).sub.3phen.

Example 3

[0091] A luminescent sheet and a laser light detecting device were produced as in Example 1 except that diethyl-2,5-dihydroxyterephthalate (available from Sigma-Aldrich, diethyl 2,5-dihydroxyterephthalate) was used instead of Eu (TFA).sub.3phen.

Comparative Example 1

[0092] A luminescent sheet and a laser light detecting device were produced as in Example 1 except that no luminescent material was used.

(Evaluation)

[0093] The laser light detecting devices obtained in the examples and comparative example were evaluated for the laser detectability by the following methods.

[0094] Table 1 shows the results.

(Laser Detectability: Direct Observation)

[0095] A laser light source, the laser light detecting device, and an observer were placed in a straight line in the stated order such that the distance between the laser light source and the laser light detecting device in the horizontal direction was 20 m and the distance between the laser light detecting device and the observer in the horizontal direction was 1 m. The heights of the laser light source and the laser light detecting device were adjusted to the eye level of the observer.

[0096] Under these conditions, laser light was applied from the laser light source such that the laser light did not directly enter the observer's eyes (aimed at the forehead). A rating of (Good) was given when the observer detected the laser light irradiation by light emission on the laser light detecting device. A rating of x (Poor) was given when the observer did not detect the irradiation.

[0097] The laser light source used was NDV4B16 (wavelength: 405 nm, output power: 300 mW) available from Nichia Corporation. The position of laser light was recorded to apply laser light to the same position in the following indirect evaluation and evaluation of notification by sound.

(Laser Detectability: Indirect Observation)

[0098] A laser light source, the laser light detecting device, and an observer were placed as in the direct observation except that the distance between the laser light detecting device and the observer was 1 m and the observer was placed at an angle of 45 in the horizontal direction relative to the center part of the glass of the laser light detecting device. The heights of the laser light source and the laser light detecting device were adjusted to the eye level of the observer. Under these conditions, laser light was applied from the laser light source to the same position as in the direct observation. A rating of (Good) was given when the observer detected the laser light irradiation by light emission on the laser light detecting device. A rating of x (Poor) was given when the observer did not detect the irradiation.

[0099] With the laser light detecting devices obtained in Examples 1 to 3, the observer detected the laser light even when the observer was not in the straight line of the laser light.

(Laser Detectability: Notification of Laser Light Irradiation by Sound)

[0100] A laser light source, the laser light detecting device, and a detection unit were placed such that the distance between the laser source and the laser light detecting device in the horizontal direction was 20 m and the distance between the laser light detecting device and the detection unit in the horizontal direction was 1 m. The detection unit was placed at an angle of 45 in the horizontal direction relative to the center of the glass of the laser light detecting device. The detection unit used was a device that takes an image of the entire surface of the laser light detecting device (luminescent sheet) and transmits a signal to the notification unit when it detects light emission of the laser light detecting device (luminescent sheet) on the obtained image. There was also provided a notification unit that provides notification by sound in response to a signal from the detection unit when the detection unit detects a laser.

[0101] Under these conditions, laser light was applied from the laser light source to the same position as in the direct observation performed earlier. A rating of (Good) was given when the laser light irradiation was detected by the sound of the notification unit. A rating of x (Poor) was given when the irradiation was not detected.

[0102] With the laser light detecting devices obtained in Examples 1 to 3, the observer detected the laser light by the sound emitted by the notification unit.

TABLE-US-00001 TABLE 1 Comparative Example 1 Example 2 Example 3 Example 1 Luminescent PVB phr 100 100 100 100 sheet 3GO phr 40 40 40 40 formulation Luminescent Eu(TFA).sub.3phen phr 0.2 material Tb(TFA).sub.3phen phr 0.2 Diethyl 2,5- phr 0.2 dihydroxyterephthalate Adhesion modifier Acetylacetone magnesium phr 0.036 0.036 0.036 0.036 Evaluation Laser detectability (direct observation) Laser detectability (indirect observation) x Laser detectability (notification by sound) x

INDUSTRIAL APPLICABILITY

[0103] The present invention can provide a laser light detecting device capable of easily detecting laser light irradiation.