1 고려대학교 산업시스템정보공학과 장 인 창, 박 동 현 Age-related decline in color perception and difficulties With daily activities-measurement, questionnaire, Optical and computer-graphics simulation studies Keiko Ishihara et al.

2 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 감소시 킨다 (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).

3 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

4 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 Questionnaire 를 만들었다 (p. 155). -subjects: 각기 다른 지역에 사는 60 세 이상 노인 1322( 남 : 584, 여 :738) 명 - four grade(never, sometimes, often, always)

5 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?

6 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”

7 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

8 2. Method(cont’d) 2.3 computer-graphics simulating how the elderly see - yellow filter 실험보다 정확하고 유연성 있는 기법을 실시하기 위해 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 color White-yellow Blue-green Blue-black Purple-brown

9 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

10 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

11 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 (Χ 2 test;p<.01, Q5;p<.05) 3.2 Experiment on misjudgment of colors by the elderly - problematic color combinations yellow/white, blue/green, dark blue/black, purple/dark red

12 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)

13 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 것 이다 (Sanders, McCormick, 1993).