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고려대학교 산업시스템정보공학과장 인 창 , 박 동 현
Age-related decline in color perception and difficultiesWith daily activities-measurement, questionnaire, Optical and computer-graphics simulation studies
Keiko Ishihara et al.
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1. Introduction
Appearance of the Problem:
- 고령화에 따른 색체지각 능력의 감소로 인한 문제 발생 .
1) 노인들은 암 순응 (dark adaptation) 의 속도가 느려지고 그 수준이 감소 .
2) 수정체가 두꺼워지며 황색이 되어 청색광의 투과를 감소시킨다 (sanders and McCormick, 1993).
3) 그러므로 , 색깔을 고르거나 맞추는데 곤란을 겪으며 , 색상환 (hue circle) 의 다른 영역보다 청록색 및 적색 영역에서
오류가 많아진다 (Verriest, Vandeyvere, Vanderdonck and Boyce, 1981).
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1. Introduction (cont’d)
General Background:-Affected by Factors that…휘도 (luminance level), 대비 (contrast), 노출시간 (exposure Time), 과녁이동 (target movement), 연령 (age), 훈련 (training)
Goal: (Ultimate aim)suggest guideline for developing products for older adult.
(This study focused on…)Graphics to simulate vision in the elderly.
Transmittance less than 40% in elderly
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2. Method
2.1 visual difficulties of the elderly
1> optical simulation by young subjects-여학생 (18 세 ) 72 명을 대상으로 노란색의 필터안경을 쓰고 일 상 생활에서 어떠한 문제점이 있는지를 연구하였다 .
2> survey of elderly subjects- 사전 실험과 기존연구를 토대로 총 10 개의 Questionnaire를 만들었다 (p. 155). -subjects: 각기 다른 지역에 사는 60 세 이상 노인 1322( 남 : 584, 여 :738) 명- four grade(never, sometimes, often, always)
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Questions…Q1: Do you have trouble in reading small print?
Q2: Do you have trouble in seeing things because they appear hazy?
Q3: Does it take time to adjust to bright lights?
Q4: Does it take time to adjust to dim lighting?
Q5: Are you dazzled if lights shine into your eyes from the side?
Q6: Do you have trouble reading signs or identifying faces while walking?
Q7: Do you bump into people or things to your side?
Q8: Do you have difficulty telling whether the flame of a gas cooker is on or off?
Q9: Do you have trouble pouring the correct quantity of water or oil into a glass or pan?
Q10: Do you fail to notice a pedestrian traffic signal until it starts blinking?
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2. Method(cont’d)
2.2 Experiment on misjudgment of colors by the elderly-computer simulation was to simulate the color confusion identified
1> subjects: 남자 6 명 (80~86 세 ), 일상생활에 도움 없이 건강 .
2> Experimental design:-34 stimuli (2 set of 17 combinations) 를 제시-조도 : 440~460 Lx-자극제시시간 1s, 눈과 자극간의 거리 60~80cm-Without wearing glasses-Respond as “same” or “different colors”
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2. Method(cont’d)
2.2 Experiment on misjudgment of colors by the elderly
3> stimulus
-10 colored tags on a piece of gray paper as a stimulus
-8 distracters – 애매한 색상들의 사각형 tag 로 구성됨
(Y - GY - G).
-2 targets – 원 tag
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2. Method(cont’d)
2.3 computer-graphics simulating how the elderly see
- yellow filter 실험보다 정확하고 유연성 있는 기법을 실시하기위해 computer graphics 를 이용한 simulation 을 사용 .
- apparatus: colorimeter
-L*(lightness), a*(green/red), b*(blue/yellow): CIE color model
- the simulation made a converted image: identical colorWhite-yellow
Blue-green
Blue-black
Purple-brown
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3. Result and discussion
3.1 Visual difficulties in daily activities of elderly
1> optical simulation by young subjects(Problems)
-appearance of the colors changed (red changed to pink)-difficult to discriminate between certain combinations of colors(blue and dark)-liquid objects were difficult to see(gas flame, pour oil)- depth perception failed- electronic displays were difficult to read
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3. Result and discussion(cont’d)
3.1 Visual difficulties in daily activities of elderly
2> survey of elderly subjects
Cluster/factor analysis (c.f. Rubin)
-Q1, Q2: focusing
-Q3~Q5: adaptation
-Q6: dynamic visual acuity
-Q7: distance
-Q8~Q10: yellowish vision
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3. Result and discussion(cont’d)
3.1 Visual difficulties in daily activities of elderly
2> survey of elderly subjects
-answers: often-always All questions are significant age effect (Χ2test;p<.01, Q5;p<.05)
3.2 Experiment on misjudgment of colors by the elderly- problematic color combinationsyellow/white,
blue/green, dark blue/black, purple/dark red
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3. Result and discussion(cont’d)
3.3 computer-graphics simulating how the elderly see
-computer-graphics simulation 을 이용하여 yellowed
Vision 을 가진 노인들이 구분할 수 없는 color 를 미리 파악할 수
있다 .
Before after(simulated)
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4. Conclusion
-노인들을 시각능력을 고려한 시각 디스플레이 설계의 guidelines(LCD, traffic sign, map etc.).
- guidelines 를 통해 safety 와 function 을 향상 .
- 노령자를 고려한 vision 설계는 모든 사람에게 이로운 것이다 (Sanders, McCormick, 1993).