• 제목/요약/키워드: 모아레 법

검색결과 26건 처리시간 0.022초

회전다면경을 이용한 줄무늬 격자 영사방법에 관한 연구 (A Study on the Grating Projection Method using Polygon Mirror)

  • 박윤창;정경민;장석준;박경근
    • 한국정밀공학회지
    • /
    • 제18권6호
    • /
    • pp.159-165
    • /
    • 2001
  • Recently Moire and PMP(Phase Measuring Profilometry) are adopted as a practical methodology for non-contact 3-D measurement of free surface. These methods extract the 3-D informations from the images of the object projected with stripe-pattern light. This paper presents a simple projector generating stripe-pattern light using expensive polygon mirror. In this projector, slit-beam is generated with a Laser diode and a rod lens and the laser diode is switched on/off synchronizing with the rotation of the polygon mirror. So its structure is very simple and light-weighted compared to the existent projection methods using several lenses and it is also easy to change the pitch and the phase of the stripe pattern. Experimental results show that the intensity profile of the stripe pattern can be approximated with sinusoidal curve by reducing the pitch of the stripe pattern.

  • PDF

노이즈 영상으로부터 모아레 기준 위상의 강인 자동 생성 방법 (A Robust Method for Automatic Generation of Moire Reference Phase from Noisy Image)

  • 고국원;김민영
    • 한국산학기술학회논문지
    • /
    • 제10권5호
    • /
    • pp.909-916
    • /
    • 2009
  • 본 연구는 위상천이 영사식 모아레 측정기의 기준 위상 측정단계에서 기준 위상의 검출 정확도를 높이기 위한 방안으로, 일반적인 N-bucket 방법이 아닌, 줄무늬 패턴 투사 영상의 직접적인 영상처리를 기반으로, 노이즈가 포함된 영상으로부터 기준 위상을 자동으로 검출하고 보정하는 방법을 다룬다. 일반적으로 기준위상을 정확히 구하기 위해서는 상대적으로 노이즈가 원천적으로 적은 고정밀도의 교정 시편과 이에 맞는 세분화된 교정방법이 필요하다. 하지만, 고가의 시편 제작비용 절감과 고정도 교정을 위한 교정시간의 단축을 위해, 상대적으로 일반 정밀도등급의 제작된 시편으로부터 획득된 영상을 이용하여, 효율적인 기준위상 교정 방법을 제안한다. 투사된 평행 라인 띠가 시편에서 반사되어 카메라로 입력되는 영상으로부터, 영상처리 라인마스크를 이용하여 격자 라인들의 중심점을 정밀하게 추출하고, 각 라인들에서 추출된 샘플링점 기반의 최소자승법을 이용하여, 라인 특징치인 기울기와 절편을 추출함으로써 실제 관측되는 격자 라인의 중심선을 획득하였으며, 획득된 중심선들을 이용하여 N-bucket 알고리즘에 적용할 수 있도록 위상을 추출한 후, 기준위상을 자동으로 생성하였다. 본 연구를 통하여 고가의 시편 제작 없이 빠르게 자동으로 기준위상을 추출할 수 있었다.

디지털 사진영상의 크기조절과정에서 유실되는 정보를 이용한 비트심도의 확장 (Research for Bit-depth Conversion Development by Detection Lost Information to Resizing Process for Digital Photography)

  • 조두희;비벡마이크;백준기;하동환
    • 한국콘텐츠학회논문지
    • /
    • 제9권4호
    • /
    • pp.189-197
    • /
    • 2009
  • 디지털 사진영상은 8비트의 음영으로 이루어져 있다. 이것은 0부터 255까지, 총 256 단계의 레벨값으로 나눠지며 자연수에 해당하는 음영만을 표현하고 소수점 이하 실수 자리의 음영은 표현할 수 없다. 하지만 영상의 크기조절과정을 수행할 때 보간 수식에 의하여 소수점이하자리가 발생하게 되지만 최종적인 출력에서는 '버림연산'에 의하여 사라지게 된다. 본 연구에서는 이렇게 버려지는 소수점 이하 자리를 이용하여 사진영상의 비트 심도를 확장할 수 있는 방법을 제시한다. 이것은 크기조절 이후 콘트라스트 조절에 사용하여 사진영상의 해상도 저하를 최소화하는데 사용한다. SFR 측정을 통하여 포토샵 결과와 비교할 경우 본 연구에서 제시하는 방법이 원본의 특성을 더 잘 유지함을 알 수 있다.

장기근속 남성 택시기사와 일반인의 근골격계 균형에 관한 비교 연구 - 모아레 체형측정법을 통해 (A Comparative Study on the Balance of Musculoskelectal System between Long-Term Employed Male Taxi Drivers and General People - through Moire Topography)

  • 임상훈;박동수;이경무;정수현;김순중
    • 한방재활의학과학회지
    • /
    • 제18권1호
    • /
    • pp.141-151
    • /
    • 2008
  • Objectives : The purpose of this study was to investigate effects of long-term taxi driving posture on the balance of musculoskelectal system. Methods : The author practiced Moire topography by using IBS-2000 for 30 male taxi drivers and general people. Then we measured difference of contour lines, difference of shoulder joint height, interval between vertical baseline of pelvis and vertical baseline of neck, ratio of thoracic curve and lumbar curve, difference of width between right and left through Moire topography. After we statistically analyzed difference of Moire topography's data between long-term employed male taxi drivers and general people. Results : 1. Taxi drivers, difference of contour lines in scapular, lumbar, gluteal region was bigger than general people and significant difference(p<0.05) was observed between subject group. 2. Taxi drivers, diference of shoulder joint height was more large than general people and significant difference(p<0.01) was observed between subject group. 3. Taxi drivers, diference of interval between vertical baseline of pelvis and vertical baseline of neck was more large than general people and significant difference((p<0.05) was observed between subject group. 4. Taxi drivers, ratio of thoracic curve was more large than general people and ratio of lumbar curve was more less than general people and significant difference(p<0.05) was observed between subject group. Conclusions : According to above results long-term taxi driving posture might cause musculoskelectal system unbalance.

초.중학생의 척추비틀림과 통증과의 관계고찰 - 경근무늬(모아레) 측정법과 설문지 조사를 통해 - (A Study of the Relationship between Spine Distortion and Pain of Elementary and Middle School Students - through moire measurement and questionnaire investigation -)

  • 유한길;신병철;민병일
    • 대한추나의학회지
    • /
    • 제2권1호
    • /
    • pp.133-142
    • /
    • 2001
  • Objectives : The aim of this study is to investigate the relationship between spinal distortion and pain in elementary and middle school students. Methods : Using the phase-shifting moire developed by KAIST(Korea Advanced Institute of Science and Technology) we measured the back surface distortion, and using questionnaire investigation, we investigated the partial pain in 1008 elementary and middle school students(532 boy students(52.8%), 476 girl students(47.2%)) in Seoul in 1999. And, we statistically analyzed the relationship between spinal distortion and partial body pain Results : This study show that the more age increase, the more the pain in head, neck, shoulder, back and low back Increase considerably among the students aged 9 to 15. The ratio of each partial body pain was 28.4%, 19.7%, 18.2%, 18.7%. 16.0% at the age of 9 and 59.7%, 67.4%, 51.8%, 51.8%, 64.4% at the age of 15 respectively. And, it was shown there was a significant correlation between spine distortion and partial body pain area. When the spinal distortion was found at the upper thoracic and cervical area, the students complained the more pain on head, neck and shoulder(p<0.05) and when the spinal distortion was found at the sacral base, the more headache(p<0.05) Conclusions : It is suggested that the significant correlation exist between the spinal distortion and pain and the pain related to spine disorder get more increase as students grow. We have to study further more about Juvenile postural distortion and it's prevention.

  • PDF

모아레 측정법과 설문지 조사를 통한 경기도 S고등학교 재학생의 신체자각증상과 배부체형에 대한 실태조사 (A Study on the Back shape and self-conscious symptoms of the students in S High school Using the Moire measurement and Questionnaire investigation)

  • 장규태;김장현;백현
    • 대한한방소아과학회지
    • /
    • 제17권2호
    • /
    • pp.55-74
    • /
    • 2003
  • Objective : The purpose of this study was to investigate the back shape and self-conscious symptoms of the students in S High school using the phase-shifting scanning grating projection Moire interferometer and Questionnaire investigations. Methods : In this study the subjects consisted of 317 pupils[168 boys(53%), 149girls(47%)] attending S high school in Sungnamsi, Kyoungkido in 2002. Their ages ranged from sixteen to eighteen. With the phase-shifting scanning grating projection moire interferometer, the posterior views of the body were taken to see if there are correlation of remainder value of the height spot of left & right shoulder blade and gluteal region in Moire topography. And using questionnaire investigation, we investigated the self-conscious symptoms. Results : 1. In questionnaire investigation, we observed that the ratios of self-conscious symptoms of girls are more than that of boys. The ratios of headache, neck pain, lower back pain, digestive symptom were more than 70% in boys and girls. 2. In Moire topography, more frequent findings of scapular region were observed that left scapular area were higher than right(in boys 69.3%, 60%, 100%, aged 16,17,18, in girls 66.8%, 40.5%, 58.8% aged 16,17,18). 3. More frequent findings of gluteal region were observed that left scapular area were higher than right(in boys 75.2%, 60%, 36.4% aged 16,17,18, in girls 61.1%, 46.8%, 64.7% aged 16,17,18) 4. More frequent findings of reminder value of the vertical lines of cervical and buttock region in Moire topography were observed that the vertical lines of cervical region were inclined to left than the vertical lines of buttock(in boys 73.3%, 92.2%, 100% aged 16,17,18, in girls 72.2%, 77.2%, 73.5% aged 16,17,18) Conclusion : From these results, we found that the self-conscious symptoms were more than in girls than boys; the ratio of headache, neck pain, Lower back pain, digestive symptom was more than the others; the back shape of high school students were not balanced in scapular and buttock region; necks were inclined to left than buttock.

  • PDF